D b and c are the exceptions and a is the answer that compensation for involuntary service means a person compensatiate to other for their services

Compensation for involuntary services
Compensation for involuntary services is not an exception to the rule No Consideration, No Contract. In order for a contract to be valid, there must be some form of consideration exchanged between the parties involved. Consideration is something of value given by each party to the other in exchange for something else. In the case of compensation for involuntary services, there is no mutual agreement or intention to enter into a contract. The services are provided without the expectation of compensation or any form of consideration, making it not a valid contract.

Love and Affection
Love and affection are not considered valid consideration in a contract. While they may be powerful motivators for individuals to enter into agreements, they do not have a monetary value or legal significance in the context of contract law. Therefore, a contract based solely on love and affection would not be enforceable in a court of law.

Contract of Agency
A contract of agency is an exception to the rule No Consideration, No Contract. In an agency relationship, one party (the agent) agrees to act on behalf of another party (the principal) and make decisions or enter into agreements on their behalf. While consideration is typically required for a contract to be valid, in the case of an agency relationship, the agent's authority to act on behalf of the principal is considered sufficient consideration to create a legally binding contract.

Gift
A gift is another exception to the rule No Consideration, No Contract. In the case of a gift, the donor voluntarily transfers ownership of property or assets to the recipient without expecting anything in return. While there is no consideration exchanged, a gift is still considered a valid contract because it is based on the intention of the donor to give the gift and the acceptance of the gift by the recipient.