Q.What are joint promises? Explain the liability of joint promisors.

A contract can be performed by the promisor, his agent or his legal representatives, so the answer is (d).

Who may perform a contract depends on its nature:

• Promisor himself — where the contract requires the promisor's personal skill (e.g. a painting or a performance), he alone must perform.
• Agent of the promisor — where personal skill is not essential, the promisor may perform through a competent agent. …

Under the Indian Contract Act, a contract can be performed by the promisor himself, by his agent (for non-personal work), or by his legal representatives on his death — so all three persons can perform it.

The persons who may perform a contract are:

• Promisor himself — required when the contract depends on personal skill (an artist, a singer).
• Agent of the promisor — where personal skill is not essential, the promisor may get performance done through a competent agent. …

On the death of one of several joint promisors, his legal representatives are jointly liable with the surviving promisors; a money promise does not become void. So A, B and C's legal representatives must jointly pay D.

Under the Indian Contract Act (Section 42), when two or more persons make a joint promise, then during their joint lives all of them must jointly fulfil the promise, and after the death of any of them, his legal representatives jointly with the survivors must fulfil it. A promise to pay a sum of money is not a personal-skill contract, so it does not end with a promisor's death.

…

A stranger to the contract cannot demand performance of a promise, option (c).

Under the Indian Contract Act, 1872, performance of a promise can normally be demanded only by the promisee or a person legally standing in the promisee's place. This flows from the doctrine of privity of contract — only parties to a contract acquire rights and obligations under it.

Therefore:

• The promisee can demand performance. …