Think which of th

A. Correct.

Federalism promotes unity while respecting the differences.

B. Incorrect.

Federal system will not hinder easier economic transaction because the rules regarding transaction is already clearly listed in the constitution.

C. Incorrect.

The federal system ensures that power of centre is limited by dividing the powers in three lists naming union, state and concurrent. But the system also promotes for strong centre. Example the strong provision of emergency is under the ambit of centre.