Which of the Following Is True with Regard to Contract

Multiple Choice

Which of the following is true with regard to contract law?

A) An option is a contract in which one person is buying a period of time within which he may accept the offer contained within the option.
B) A newspaper notice offering to pay a reward for the return of lost kittens is an invitation to treat.
C) A revocation is effective only when sent.
D) An important criterion for determining the place of the contract is the place where the offer is mailed.
E) A counter-offer does not end an offer.