Assertion : Colloidal particles show Brownian movement. Reason : Brownian movement arises because of the impact of the molecules of the dispersion medium with the colloidal particles.

• 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.