If 5x + 3y + 7z = 5, 3x + 2by + 2z = 9, 7x + 2y + 10z = 5, be a system of equations, then

A

It has only trivial solution, x = 0, y = 0, z = 0

B

System is consistent and has infinite solution

C

System is consistent and has unique solution

D

System is inconsistent