All of the following are reasons that Travis becomes angry with Eckels for stepping off the path except that...

a) Eckels has disobeyed Travis's orders.

b) Travis fears that Eckels may have changed history.

c) Travis fears that Time Safari will have to go out of business.

d) Travis fears that they won't be allowed to return to their world.

By the way, for the answer to this question I believe I'm clueless, that's why I chose clueless.