Which of the following is correct for a parallel plate capacitor of separation 'd' when a slab of material of dielectric constant $k$ has the same area as the plate of capacitor but has a thickness d/2 is inserted between the plates?

A. Its capacitance decreases
B. Its capacitance increases
C. $C=C_0(\frac{2k}{k+1})$
D. $C=C_0(\frac{k+1}{2k})$
E. Charge remains same.

Choose the correct answer from the options given below:

B, C and E Only

The correct answer is Option (4) → B, C and E Only