ANS:B - 30%

The Reserve Bank of India (RBI) has lowered the maximum risk for custodian banks issuing irrevocable payment commitments (IPCs) from 50% to 30%. This decision follows the reduction in trade settlement time from T+2 to T+1 and T+0 for select equities by stock exchanges. The revised guidelines aim to mitigate risks associated with potential downward price movements of equities purchased by foreign institutional investors/mutual funds over two successive days from the trade date.