According to the Basel Committee on Banking Supervision (BCBS), a sound KYC program should contain four essential elements: (i) customer acceptance policy; (ii) customer identification; (iii) on-going monitoring of higher risk accounts; and (iv) risk management1. These elements correspond to the options B in the question, as customer identification involves verifying the identity and beneficial ownership of the customers, risk assessment involves determining the level of risk posed by the customers and their activities, customer screening involves checking the customers against relevant sanctions and watch lists, and monitoring involves reviewing the customers' transactions and behavior for any anomalies or red flags.
References:
* Consolidated KYC Risk Management - Bank for International Settlements Reference: https://www.bis.org/publ/bcbs77.pdf