Context: Read the passage. Then answer the question.

Alcon blue butterflies spend the first part of their lives as caterpillars that live with Myrmica ants. When a caterpillar lives with the ants, it mimics, or pretends to be, an ant. The caterpillar can mimic the ants by copying their smell. The caterpillar can also make noises that make it sound like a queen ant. Queen ants receive more food and better protection than any other ants in the nest.
So, when the caterpillar mimics an ant, the ants feed and protect the caterpillar instead of other ants in the nest.
Figure: a Myrmica ant caring for an Alcon blue caterpillar.
Which type of relationship is formed when an Alcon blue caterpillar lives in a Myrmica ant nest?
A. parasitic
B. mutualistic
C. commensal
Select the correct answer from the provided options and reply with the letter associated with it.
Answer: A