Final answer:
The correct answer is option a. Chaya's early role in the Resistance is as a courier, which is essential for moving messages and supplies securely and coordinating efforts within the movement.
Step-by-step explanation:
In the book Resistance, Chaya's role early in her time with the Resistance is crucial for the movement's communication and logistics. Her job is to serve as a courier. This role involves transporting messages, documents, and sometimes supplies between different groups of resistance fighters, as well as with contacts outside their organization.
This is a highly dangerous job because it requires moving throughout occupied territories and maintaining secrecy to avoid detection by the enemy. By being a courier, Chaya helps to ensure that vital information and materials are delivered safely, enabling the resistance to coordinate their efforts against the oppressors effectively.