Tritium (³H) Is a Heavy Isotope of Hydrogen, Composed of One

Multiple Choice

Tritium (³H) is a heavy isotope of hydrogen, composed of one proton and two neutrons. Tritium decays into ³He, a light isotope of helium, composed of two protons and one neutron, through the reaction . ${ }^{3} H \rightarrow{ }^{3} H e+\bar{e}+\bar{v}$ The production of an electron and an antineutrino in this decay shows that the reaction was governed by the:

A) electromagnetic force.
B) gravitational force.
C) strong force.
D) weak force.