Select the most appropriate synonym of the underlined word in the given sentence.
Mr. Satterthwaite was shrewd enough to penetrate her meaning.

The word 'shrewd' means having or showing sharp powers of judgment; astute, sharp-witted, or smart. Among the given options, 'Smart' is the closest synonym.
* 'Aged' means old.
* 'Funny' means causing laughter or amusement.
* 'Innocent' means free from guilt or guile.