Why or how, do electrons receive a positive charge during beta decay?

Beta decay occurs when a nucleus is unstable because it has too many or too few neutrons relative to protons. The nucleus emits a beta particle and energy.  In beta-minus decay, a neutron breaks down to a proton and an electron, and the electron is emitted from the nucleus.

Explanation:

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.