Assertion : If earth were a hollow sphere, gravitational field intensity at any point inside the earth would be zero. Reason : Net force on a body inside the sphere is zero.

(a)       If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)       If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)        If assertion is true but reason is false.

(d)       If the assertion and reason both are false.

(e)       If assertion is false but reason is true.

Answer: a