What is ‘Central Equipment Identify Register’?

The correct answer is Option (1) → A portal launched by the Government of India to block and trace mobile phones.

Out of the options you provided, the closest function to the Central Equipment Identity Register (CEIR) is:

☀ A portal launched by the Government of India to block and trace mobile phones.

CEIR's primary purpose is indeed to track and block stolen or lost mobile phones, not criminal activities in general, tax compliance, or illegal immigration. It achieves this by keeping a database of unique mobile identifiers and allowing network operators to check if a device is blacklisted.