Her new glasses make her look rather owlish.

Answer: Option B

Foolish : lacking good sense or judgement; unwise.
Solemn : formal and dignified.
Silly : having or showing a lack of common sense or judgement; absurd and foolish.
Stupid : having or showing a great lack of intelligence or common sense.
Owlish : like an owl, especially in appearing to be solemn or wise.

Synonym of Owlish is Solemn