Fact 1: Some insects can use their antennae to detect sound.

Fact 2: Insects have 2 antennae.

Given the two facts above, answer the question "How many appendages do insects have to detect sound?" with the following options: 
- ears
 - Three
 - None
 - legs
 - 12
 - six
 - Two
 - One


 

       Two  