Select the word which means the same as the group of words given.
Unit of weight for precious stones

Correct option is C

The correct one-word substitution is "Carat."
Explanation: A carat is a standard unit of weight for measuring gemstones and pearls, equivalent to 200 milligrams (रत्नों का वजन मापने की इकाई).
Example: The diamond weighs five carats.
Meanings of the other options:
· Pure (a): Not mixed with anything else; unadulterated (शुद्ध).
· Reliable (b): Able to be trusted or depended on (विश्वसनीय).
· Accurate (d): Correct in all details; exact (सटीक).