One-Word Substitution

'Scullery' is a room in which dishes and utensils are cleaned.

Ignoramus means an ignorant person.
 

Option (2) is correct.

Option (2) is correct.

Option (4) is correct.

Irreparable refers to something that cannot be repaired, fixed, or made good again. It is the standard term for a loss that is permanent.

Aborigines are the people who have been in a country since the earliest known times. They are the indigenous or original inhabitants.

An incendiary is a person who maliciously sets fire to property. The term comes from the Latin 'incendere' meaning to set fire.

Nescience is a formal term for the lack of knowledge or ignorance. It is the direct opposite of omniscience (all-knowing).

A mimeograph is an old-fashioned printing machine that uses a stencil to make multiple copies of a document.

Camouflage is the use of materials, colors, or illumination to hide or disguise the presence of something. It makes objects difficult to recognize.

Orology is the scientific study of mountains. It is derived from the Greek 'oros' (mountain).

A pedestrian is a person who is walking rather than traveling in a vehicle. It comes from the Latin 'pedis' (foot).

An aviary is a large cage or building for keeping birds. It is distinct from an apiary, which is for bees.

'Archipelago' describes a sea which abounds in Islands.

A curator is a person in charge of a museum or a collection of exhibits. They are responsible for the care and management of the items.

Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth.

Pharmacology is the branch of medicine concerned with the uses, effects, and modes of action of drugs. It is the science of pharmacy.

Illegible is the specific term used to describe handwriting that cannot be read. Illegal refers to something against the law, while obscure means unclear or hard to understand in a general sense.

A hedonist is defined as a person who believes that the pursuit of pleasure is the most important thing in life. An epicure is someone who takes particular pleasure in fine food and drink, which is a narrower definition.

Eloquence refers to fluent or persuasive speaking or writing. The other options are general terms for communication or speech acts.

 A person who is generally only after material things irrespective of culture events is a materialist. A philistine is someone who is indifferent to cultural events, but this does not mean the a philistine is particularly materialist. Hence, materialist is correct. 

Anarchy is the state of a society being freely constituted without authorities or a governing body. Democracy, autocracy, and aristocracy all describe specific forms of government.

A cacographist is someone who is bad at spelling or writes poorly. Calligraphist refers to someone skilled in beautiful handwriting.

An equestrian is a person who is skilled in riding horses. A jockey is specifically a professional horse rider in races, which is a more specific subset.