____ bank has sole monopoly in issue of currency.

Central bank has sole monopoly in issue of currency.

Explanation:-

One of the functions of the Central Bank is:

Current Authority (or Bank of Issue):-

The Central Bank has the sole authority for the issue of currency in the country.

In India Reserve Bank of India (RBI) has the sole right of issuing paper currency notes.

All the currency issued by the Central Bank is its monetary liability, i.e., the Central Bank is obliged to back the currency with assets of equal value to enhance public confidence in paper currency.

Note:- Here Assets usually consist of gold coins, gold bullions, foreign securities, and domestic government’s local currency securities.