Question

what does zaroff mean when he nods to ivan?
a he is threatening rainsford to join him as he hunts other people.
b he is giving rainsford the choice to join his hunt or be hurt by ivan, which is the choice he gives his other victims.
c he is threatening rainsford not to tell his secret if he lets him leave the island.
d he is agreeing with ivan in that there is no escape off the island.

Explanation:

In the story context, Zaroff gives victims the choice to either join his hunt or be hurt by Ivan. His nod to Ivan is related to this ultimatum - like signaling Ivan's readiness to act if Rainsford doesn't choose to join.

Answer:

B. He is giving Rainsford the choice to join his hunt or be hurt by Ivan, which is the choice he gives his other victims.