Assertion: Cultural diversity can present tough challenges.
Reason: The cultural identities are very powerful. 

Both A and R are true and R is the correct explanation of A.

The correct answer is Option 1: Both A and R are true and R is the correct explanation of A.

Assertion: Cultural diversity can present tough challenges. — True. Cultural diversity brings together different social groups and communities, each with its own language, religion, caste, race or other cultural markers. When these communities compete over resources, recognition or rights, differences may lead to tensions and conflicts, making cultural diversity a challenge.

Reason: Cultural identities are very powerful. — True. Cultural identities evoke a strong sense of belonging and can mobilise large numbers of people. Because individuals are deeply attached to their cultural identities, issues involving these identities often generate intense emotions and collective action.

Why is the Reason the correct explanation of the Assertion?
The Reason directly explains the Assertion. Cultural diversity becomes challenging precisely because cultural identities are powerful, capable of arousing intense passions and mobilising large numbers of people. This can intensify competition and conflict among communities, making the management of cultural diversity difficult.