When the person to whom the proposal is made signifies his assent thereto, the proposal is said to be accepted. A proposal, when accepted:

Correct option is B

According to Section 2(b) of the Indian Contract Act, 1872, when the person to whom the proposal is made signifies his assent thereto, the proposal is said to be accepted. A proposal, when accepted, becomes a promise. As per Section 2(h), an agreement enforceable by law is a contract. Thus, a proposal becomes a contract once it is accepted and is supported by consideration and lawful object, fulfilling all the essentials of a valid contract.

Information Booster:
Section 2(a): Definition of proposal
Section 2(b): Acceptance of proposal
Section 2(e): Agreement = promise + consideration
Section 2(h): Contract = agreement enforceable by law

Additional Information:
The formation of a contract requires a lawful offer and acceptance, lawful consideration, capacity to contract, and free consent, among other essentials under Section 10 of the Indian Contract Act, 1872.