Correct option is A
The correct answer is (A) Carbon-12.
Atomic masses are determined using the Carbon-12 isotope as the standard reference. The atomic mass unit (amu), or dalton (Da), is based on the mass of the Carbon-12 isotope, which is defined as exactly 12 atomic mass units.
Information Booster:
Carbon-12 is the most stable and abundant isotope of carbon, making it a natural and convenient reference for atomic mass measurements.
The atomic mass unit (amu) helps in expressing the mass of atoms and molecules in a consistent way across different elements.
Additional Information:
Carbon-13 (Option B) and Carbon-14 (Option C) are other isotopes of carbon but are not used as standards for atomic mass. Carbon-13 is used in nuclear magnetic resonance (NMR) and radiocarbon dating, while Carbon-14 is commonly associated with radiocarbon dating.
Carbon-11 (Option D) and Carbon-15 (Option E) are radioactive isotopes and not used as standard references for atomic mass determination.
