1. (a) That's right. An agency of necessity may arise when a wife is deserted by her husband and does not have the means to obtain necessities for herself or her children. In such circumstances, the wife is recognised as the agent of the husband for the purposes of obtaining such necessities.

In this case, A and B are married, B has been deserted by A, and the things she acquires as A's agent are necessities rather than luxuries. Accordingly, A would be legally bound to pay for those things.

Note: It is thought that the agency of necessity of an abandoned spouse can be distinguished from the agency that is presumed under the common law to exist between spouses who are living together.