Gruber and Colleagues' (2009) Work with Chimps Involving a Deep

Multiple Choice

Gruber and colleagues' (2009) work with chimps involving a deep drilled hole filled with honey found that chimps from the troops that usually used leaves to obtain food used _____ in the new context, while chimps that that usually used sticks used ______ in the new context.

A) Leaves; sticks
B) Their fingers; their fingers
C) Sticks; sticks
D) Leaves; leaves