Which idiom best describes the paragraph?

When Jeff let it slip that Aunt Ellen had loaned him the last bit of cash he needed to purchase a new bike, his brother Tony exploded. From then on Tony tried to pick fights and started telling lies about Jeff. Jeff didn't see how it would ever end. Yet he was positive Aunt Ellen would have gladly helped Tony, too.

A.
writing on the wall

B.
at the end of my rope

C.
open a can of worms

D.
to swallow something hook, line, and sinker