Determine whether the given set S is a subspace of the vector space V.
A. VR", and S is the set of solutions to the homogeneous linear system Az = 0 where A is a fixed m. x n matrix.
B. VP, and S is the subset of P consisting of those polynomials satisfying p(0) = 0.
C. VC2(I), and S is the subset of V consisting of those functions satisfying the differential equation y" 4y + 3y = 0.
D. VR³, and S is the set of vectors (21, 22, 23) in V satisfying 21 522+234