the element which is used as the base to calculate the atomic mass of all elements is _____.\na carbon\nb…

the element which is used as the base to calculate the atomic mass of all elements is _____.\na carbon\nb oxygen\nc fluorine\nd none of the above
Answer
Brief Explanations:
In chemistry, carbon - 12 is the standard for calculating atomic masses. One - twelfth the mass of a carbon - 12 atom is defined as one atomic mass unit (amu).
Answer:
A. Carbon