Determine whether the given set S is a subspace of the vector space V. A. V=P3, and S is the subset of P3 consisting of all polynomials of the form p(x)=x2+c. B. V=C2(I), and S is the subset of V consisting of those functions satisfying the differential equation y′′=0.C. V is the vector space of all real-valued functions defined on the interval [a, b], and S is the subset of V consisting of those functions satisfying f(a)=f(b).D. V=Mn(R), and S is the subset of all diagonal matrices. E. V=Rn, and S is the set of solutions to the homogeneous linear system Ax=0 where A is a fixed m×n matrix. F. V is the vector space of all real-valued functions defined on the interval [a, b], and S is the subset of V consisting of those functions satisfying f(a)=6.G. V=Mn(R), and S is the subset of all nonsingular matrices.