Step 1: Understanding the Question
The question asks to identify the main Indian agency responsible for investigating cases under the Prevention of Money Laundering Act (PMLA), 2002.
Step 2: Defining the Roles of the Agencies
(A) Income Tax Department: Primarily deals with matters of direct taxation, including income tax, and investigates tax evasion.
(B) Enforcement Directorate (ED): This is a specialized financial investigation agency under the Department of Revenue, Ministry of Finance. It is the primary agency responsible for enforcing two key laws: the Foreign Exchange Management Act (FEMA) and the Prevention of Money Laundering Act (PMLA).
(C) Serious Fraud Investigation Organization (SFIO): Investigates complex white-collar crimes and corporate fraud, under the Ministry of Corporate Affairs.
(D) Central Bureau of Investigation (CBI): This is India's premier investigating agency for a wide variety of crimes, including corruption, economic offenses, and special crimes. While it can investigate the predicate offenses that lead to money laundering, the ED is the designated authority for PMLA cases.
Step 3: Final Answer
The Enforcement Directorate (ED) is the primary agency in India for investigating cases of money laundering under the PMLA, 2002. Therefore, option (B) is the correct answer.