अज्ञात मात्रा को तुलना द्वारा मापने के लिए उपयोग की जाने वाली ज्ञात निश्चित मात्रा कहलाती है: , The known fixed quantity used to measure the unknown quantity by comparison is called:

Solution

A. Unit

Explanation

The known fixed quantity used to measure the unknown quantity by comparison is called unit.