Choose the correct option to fill in the blank in the given sentence:-

The professor gave a _____ explanation, making even the most complex concepts easy to understand.

coherent

The correct answer is Option (1) → coherent

"Coherent" means logical and well-organized, making it easy to follow and understand — which matches the context of explaining complex concepts clearly.

• perplexing: (adjective) completely baffling; very confusing. This is the opposite of making concepts easy to understand.

• vague: (adjective) of uncertain, indefinite, or unclear character or meaning. This would make concepts harder, not easier, to understand.

• superficial: (adjective) existing or occurring on or at the surface; not thorough, deep, or complete. A superficial explanation would not make complex concepts easy to understand.