Assertion : When a dielectric slab of dielectric constant K is introduced between the plates after disconnecting the battery, energy stored in the capacitor decreases.
Reason : Potential difference between two plates decrease by a factor K ad charge remains the same, so energy decreases.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of Assertion
B. If both Assertion and Reason are true but the Reason is not the correct explanation of Assertion
C. If Assertion is true but Reason is false
D. If both both Assertion and Reason are false