Identify the incorrectly punctuated sentence.

A. He is a tough young man.
B. Many friendly, eager students are here.
C. We try to be honest polite people.
D. He’s an intelligent, athletic sophomore.

C. We try to be honest polite people. (missing comma between "honest" and "polite")

The incorrectly punctuated sentence is C. "We try to be honest polite people."