Answer:
A. weak : frail
Explanation:
"weak" and "frail" are the best option among the words listed in the question.
"Thin" and "gaunt" refer to they physical appearance of a person, who looks "frail" or "weak". The words "weak" or "frail" having more of a figurative meaning, that is still similar to "thin" or "gaunt".
To understand is to perceive the intended meaning of ( words, a language or speaker).
A satire on the social beliefs and the economic conditions of Europe at the time
