Malcom wants to kill Macbeth for revenge after Macbeth killed Macduff's entire family, who was Malcom's friend. (Also to become king.)
Answer: B
Explanation:
I don't know much about gerunds and I'm not very good at explaining but a gerund is a form that is derived from a verb but it functions as a noun.
Chocolate was learned about when Europeans explored Africa. I do not know how did found out. I hope this answers the "when" part of the question