Assertion(A) One atomic mass unit is defined as one twelth of the mass of one carbon-12 atom.
Reason(R) Carbon-12 isotope is the most abundant isotope of carbon and has been chosen as standard.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not the correct explanation of A
C. A is true but R is false
D. Both A and R are false

Answer

B

Explanation

Correct explanation. Choosing C-12 as the standard, the relative masses of the atoms come out to be close to whole number values.