This question was posed to me by my school teacher while I was bunking the class.
I’m obligated to ask this question of Mole Concept and Molar Masses in division Chemistry Basic Concepts of Chemistry – Class 11
The best I can explain: In the above given equation 1 u = Mu/NA; “u” refers to the atomic mass unit, Mu refers to molar mass constant(Its value is defined to be 1 g/mol in SI units). 1 u = Ma/NA = 1.660539040 x 10^-27 kg. Hence the above statement is true.