The definition of one atomic mass unit and its value is
(a) 1/12\(^{ th}\) mass of an atom of oxygen-16,1amu \(=1.6\times10^{-19}\)Kg
(b) 1/16\(^{ th}\) the mass of an atom of carbon-12,1amu = \(9.1\times10^{-31}\)Kg
(c) 1/12\(^{ th}\) the mass of an atom of carbon-12,1amu =\(1.66\times10^{-27}\)Kg
(d) The mass of helium nucleus, 1amu=\(3.2\times10^{-27}\)Kg