There Are Two Goods X and Y

There are two goods X and Y. In which of the following cases will good X have the most price- elastic supply?

A) If it is less costly to shift from producing X to another product than it is to shift from Y to another product.
B) A higher proportion of national income is spent on X than on Y.
C) The cost of producing extra units increases more rapidly in the case of X than in the case of Y.
D) Consumers find it easier to find alternatives for X than for Y.