English

The passive voice of 'Who taught you English?' is 'By whom was English taught to you?' because it correctly changes the active subject 'Who' into the agent introduced by 'By whom' and maintains proper verb tense and structure.

The word 'thrifty' means being careful with money or resources, which is synonymous with 'frugal'. The other options do not share this meaning.

An 'Anarchist' is a person who seeks to destroy all government and order, which directly matches the definition in the question. The other options do not fit this meaning.

The comparative degree of an adjective is typically followed by the word 'than' to compare two things, as in 'taller than' or 'smarter than.'

The correct preposition to use with 'appropriate' in this context is 'to', as in 'appropriate to the event.' This phrase means the speech was not suitable for the event.

The idiom "once in a blue moon" means something that happens very rarely or infrequently. Therefore, the correct meaning is "Rarely."

The idiom "pour cold water on" means to discourage or dampen enthusiasm or excitement about something. It is used when someone tries to reduce the enthusiasm or optimism of others.

The word 'reprobate' means morally unprincipled or wicked. Its antonym is 'virtuous,' which means having high moral standards. Therefore, option B is the correct antonym.

The antonym of 'brevity' (meaning shortness or conciseness) is 'verbosity,' which means using more words than necessary or wordiness. Therefore, option B is correct.

The word 'maladroit' means clumsy or awkward, so the synonym is 'Clumsy'. The other options have opposite or unrelated meanings.