Spellings

Convertible is the correct spelling. The word follows standard English spelling rules with 'vert' (from Latin vertere - to turn) and the suffix '-ible'. The other options incorrectly place vowels or use wrong letters.

Accessible is the correct spelling. The word has a double 's' after the prefix 'ac-' because it comes from Latin 'accessibilis'. The 'ss' pattern is consistent with related words like access and accession.

 Reliable is the correct spelling.

Inadmissible is the correct spelling. The prefix 'in-' meaning 'not' combines with 'admissible'. The 'ss' is retained from the root word 'admit', following standard English spelling rules.

Manageable is the correct spelling. When adding '-able' to words ending in silent 'e', the 'e' is usually dropped (manage + able = manageable). The 'g' remains soft without needing 'e'.

Invulnerable is the correct spelling. The prefix 'in-' combines with 'vulnerable'. The 'n' in 'un' is retained, and 'able' remains unchanged - it's not a suffix addition but direct prefix attachment.

Air-pump is the correct spelling. It's a compound word with 'air' and 'pump' joined by a hyphen. The 'pump' spelling is standard, not 'pamp' or other variations. 'Air' spells with 'ai' not 'hair' or 'heir'.

Incorrigible is the correct spelling. The word combines 'in-' prefix with 'corrigible' (from Latin corrigere - to correct). It keeps the 'rr' and ends with 'ible', maintaining the original Latin structure.

Belt-driven is the correct spelling. When 'belt' and 'driven' combine as a compound adjective, they are hyphenated. The word 'driven' (from drive) keeps its standard spelling with 'v' not 'f'.

The correct spelling is 'Visible' - derived from Latin 'visibilis' meaning 'that can be seen'. The other options add unnecessary letters like 'Veesible', 'Visibal', and 'Vessibal' which are not standard English spellings.

Inflexible is the correct spelling - from Latin 'inflexibilis' meaning not bendable. The middle letter is 'e' not 'a' (Inflaxible), and the ending is '-ible' not '-ibal' (Inflaxibal). The 'x' in Inflaxible/Inflaxabal is incorrect - the root is 'flex' from Latin 'flectere' (to bend).

Dull-eyed is the correct spelling - it's a compound adjective describing someone with dull or lifeless eyes. The word 'dull' uses 'u' not 'a' (Dall-eyed), and the past tense of 'eye' is 'eyed' not 'iyed' or 'iyeed'. The hyphen connects the two parts correctly.

Fire-brigade is the correct spelling - it refers to a fire department or firefighting service. 'Bridge' is a different word entirely (a structure), so 'Firebridge' is wrong. The correct term has 'brigade' (an organized group) and is properly hyphenated as a compound noun.

Debenture-holder is the correct spelling - a debenture is a type of debt instrument, and a debenture-holder is someone who holds it. The root is 'debenture' (not 'dibenture' or 'dabenture'), and 'holder' (not 'halder'). The hyphen correctly connects the compound noun.

Full-fledged is the correct spelling - meaning completely developed or mature. It comes from 'fledge' (to grow feathers), so it's '-fledged' not '-fladged'. The word is 'full' not 'ful', and it requires a hyphen as a compound adjective. 'Fullfledged' incorrectly omits the hyphen.

Ground-off is the correct spelling - it could describe something removed by grinding. 'Ground' (from grind) uses 'ou' not 'oa' (Groand), and 'off' is spelled with 'o' not 'a' (Ground-aff). The hyphen connects the verb participle and preposition correctly.

Long-stroke is the correct spelling - a compound describing something with a long stroke. 'Long' uses 'o' not 'a' (Langstroke), and 'stroke' uses 'o' not 'e' (Longstoke). The hyphen properly connects the two words in this compound term.

Man-of-war is the correct spelling - it's a compound noun referring to a warship or a jellyfish. It uses 'Man' not 'Mean', 'of' not 'off', and 'war' not 'waar'. The hyphens correctly connect all three parts of this multi-word compound. 'Man of war' without hyphens is incorrect.

Head-dress is the correct spelling - referring to clothing or ornamentation worn on the head. 'Head' uses 'ea' not 'ae' (Haedress), and the full word is 'dress' not 'dres' (Headdres). The hyphen connects the compound noun correctly.

Plumb-level is the correct spelling - 'plumb' means perfectly vertical or true, and it's used with 'level' in surveying and construction. 'Plumb' has 'u' not 'a' (Plamb), and it's 'level' not 'laval' or 'avel'. The hyphen connects the compound term correctly.

Radio-active is the correct spelling - describing materials that emit radiation. 'Radio' is spelled with 'dio' not 'deo' (Radeo), and 'active' uses 'ac' not 'acc' (Radioacctive). The hyphen connects the compound adjective correctly, though 'radioactive' as one word is also acceptable.

Son-in-law is the correct spelling - a family relationship term referring to your daughter's husband. It uses 'Son' not 'San', and 'in' not 'in' or 'il'. The hyphens correctly connect all three parts of this standard family relationship compound. 'Saninlow' and 'Sanilow' are phonetically incorrect.

The compound word uses 'knock' with a double 'k' followed by 'out'. Options A and C incorrectly spell 'knock' with a single 'k', while D incorrectly spells the full word.

'Hue-and-cry' is the correct spelling of this idiomatic expression. Option B misspells 'hue' as 'hua' and 'cry' as 'cary', C misspells both words, and D incorrectly combines them.

'Non-availability' is correctly spelled with 'non-' prefix and 'availability'. Option B misspells 'availability' as 'avalability', C is garbled text, and D is incorrect since A is valid.