Mr. X was advised by an architect to make outer walls of his house with hollow bricks . The correct reason is that such walls
(a) make the building stronger
(b) Help keeping inside cooler in summer and warmer in winter
(c ) Prevent seepage of moisture from outside
(d) Protect the building from lightning

Options

A. make the building stronger
B. Help keeping inside coller in summer and warmer in winter
C. Prevent seepage of moisture from ouutside
D. Protec the building from lightning