1.65. please tell me the explaination and option for this

1.65. A matrix A = (a) m x n is said to be strictly diagonal if j| slaul for i = 1, 2,..., n. Let B be a 14 x 15 matrix such that B contains a strictly diagonal submatrix of order 9. Then i) rank B =9 (ii) 14 2 rank B 29 (iv)rank B s 9. (i) rank B <9