Question

question 9
primates that are active at night are called
diurnal.
nocturnal.
undergraduates.
old - world monkeys.

Explanation:

The term "nocturnal" refers to animals that are active during the night. Diurnal animals are active during the day. "Undergraduates" are students, not a term for primate activity patterns. Old - world monkeys can be either diurnal or nocturnal but are a group of primates, not a term for night - active behavior.

Answer:

B. nocturnal