The primary function of the is to collect sounds and channel them into the interior of the ear.

Answer;
The primary function of the pinnae  is to collect sounds and channel them into the interior of the ear.

Explanation;
The pinna is the visible part and the external part of the ear, which has a special helical shape. It is actually the first part of the ear that reacts to sound. It acts as a kind of funnel which helps in directing the sound waves into the interior of the ear.