What is the delta of a forward contract on a non-dividend paying stock?

A forward contract is a derivative contract, and has a delta of 1. Therefore Choice 'd' is the correct answer. This is because the value of a forward contract is given by S - Ke^(-rt), where S is the current spot price, r the risk free rate, K the forward price, and t the time to maturity. As S changes from S to (S + δS), the value changes to (S + δS) - Ke^(-rt), ie the change in value is exactly δS in response to a change in the price of the underlying by δS. Therefore the forward contract has a delta of 1.

All other choices are incorrect.

Note that this is different from the delta of a futures contract which is different from 1, and equal to e^(rt), a number greater than 1.