The answer is A. this process is only in the research phase
The process of fusion involves merging of atomic nuclei to
form heavier nuclei resulting in the release of enormous amounts of energy.
Fusion takes place when two low mass isotopes, typically isotopes of hydrogen,
unite under conditions of extreme pressure and temperature. Scientists continue
to work on controlling nuclear fusion in an effort to make a fusion reactor to
produce electricity. However, progress is slow due to challenges with
understanding how to control the reaction in a contained space.
