A pen is a tool used by a poet. A needle is a tool used by a tailor. The answer is not choice a, b, or c because none is a person and therefore cannot complete the analogy.
An artist makes paintings; a senator makes laws. The answer is not choice a because an attorney does not make laws and a senator is not an attorney. Choice c is incorrect because a senator is not a politician. Constituents (choice d) is also incorrect because a senator serves his or her constituents.