Choice "C" is correct. Generally, one can assign rights under a contract with the exception of personal services or when the assignment increases the obligor's risk. The right to receive money is a very common right that is assignable.
Choice "a" is incorrect. Generally, the right to receive personal services is not assignable.
Choice "b" is incorrect. Generally one cannot assign a right if the assignment will vary the obligor's risk. Insurance policies are contracts involving the assessment of risk. Therefore, coverage rights under these contracts are not assignable.
Choice "d" is incorrect. If a statute prohibits assignment of a particular right then, obviously, the right is not assignable by operation of law.