One Word Substitution

The intentional and unlawful killing of a person is called "murder".

A person who loves mankind and works for their well being is a "philanthropist".

"Phrenology" is the study of the external form of cranium.

Pedagogy is the method and practice of teaching, especially as an academic subject or theoretical concept.

A boss is a person in charge of a worker or organization. While 'chief' is similar, 'boss' is the most common term for one who controls workers.

A simpleton is defined as a foolish or gullible person who is easily deceived. Other options like bigot or cripple refer to different traits or physical conditions.

A gaoler (or jailer) is the person in charge of a prison. The other terms refer to hunters, grazers, or mentors, which are unrelated to prison management.

Reasoning from parallel cases is called "analogy".

"Penology" is the study of punishment and prison management. 

A pugilist is a professional boxer. The term comes from the Latin word pugil, meaning a fighter.

Phonology is the branch of linguistics that studies the sound systems of languages. Gastronomy relates to food, and gerontology relates to aging.

Deontology is the ethical theory that uses rules to distinguish right from wrong, focusing on duties and obligations. It is distinct from medical professions like surgeon or physician.

Trichology is the scientific study of hair and scalp health. Taxonomy is the classification of organisms, and polemics is the study of controversial arguments.

A janitor is a person employed to look after the maintenance and cleaning of a building. The other options refer to horse riders, ordinary people, or learned individuals.

Sphygmology is the study of the pulse. While the option provided is 'Sphygmic', it is the adjective form related to the science of the pulse.

An 'ironmonger' is a dealer in hardware and metal goods. 'Hater dasher' appears to be nonsense, 'nanny' is a child caregiver, and 'miner' works in mines extracting ores.

Horology is the study and measurement of time. Hymnology is the study of hymns, and graphology is the study of handwriting.

A chiropodist (also known as a podiatrist) is a medical professional who specializes in the care and treatment of feet.

A philatelist is a person who collects or studies postage stamps. The other options describe skeptics, vendors, or devotees.

"Limnology" is study of the fresh water and their inhabitants.

Silviculture is the practice of controlling the growth, composition, and quality of forests. Topiary refers to the pruning of plants into shapes.

A naturopath is a practitioner who emphasizes natural treatments, diet, and exercise over conventional medicine.

Lexicography is the process or art of compiling dictionaries. The other options relate to water therapy, future studies, or handwriting analysis.

An 'intern' is a medical graduate who assists physicians or surgeons while completing training. 'Oncologist' treats cancer, while 'favor' and 'calmest' are not occupations.

A 'midwife' is trained to assist women during childbirth and provide prenatal care. 'Urologist' treats urinary tract conditions, 'intern' is a junior doctor, and 'none' is not a valid answer.