The Central Depository Services (India) Limited (CDSL) has become the first and only listed depository in India to register more than 60 million ____accounts.

The correct answer is Demat.

Step-by-Step Explanation:

1. Understanding Depository Services:
In India, a depository is an organization that holds securities (like shares, debentures, government securities, mutual funds, etc.) of investors in electronic form. There are two primary depositories in India: National Securities Depository Limited (NSDL) and Central Depository Services (India) Limited (CDSL).

2. Identifying the Type of Account:
Depositories hold these financial securities in specialized accounts called Demat accounts (short for "dematerialized accounts"). Unlike commercial banks that handle transactional accounts like Current, Savings, Recurring, or NRI bank accounts, depositories specifically manage Demat accounts to facilitate online trading and investment in the stock market.

3. Context of the Milestone:
CDSL, which is the only listed depository in India (traded on the National Stock Exchange), registered a major milestone by active account registration. The milestone of reaching over 60 million accounts refers to active Demat accounts opened by retail and institutional investors to hold shares and securities in electronic form.