Choose the alternative which can replace the bold word without changing the meaning of the sentence.
Her astute observations during the meeting impressed everyone.

The word "astute" means having the ability to accurately assess situations or people and turn them to one's advantage, often implying sharpness or cleverness. "Clever" is the closest synonym, conveying the same idea of quick and smart judgment.
The other options are incorrect:
(1) Foolish and (4) Clumsy are antonyms of "astute."
(3) Indifferent does not match the context of being observant or sharp.
Therefore, "clever" correctly replaces "astute" in the given sentence.