Which is most likely why many scientists reject the cold fusion theory?
a.) there is too much waste involved in the process.
b.) cold fusion experiments have been conducted at room temperature only.
c.) the process does not produce enough energy to meet the needs of modern humans.
d.) the original results have not been replicated consistently and reliably.

The answer is D. The cold fusion theory was first brought about by Stanley Pons and Martin Fleischmann in 1989. They claimed that their unintended experiment has produced enormous amounts energy at room temperatures that could only be explained by cold fusion theory. The experiment involved the electrolysis of heavy water (with deuterium rather than hydrogen isotope) on a palladium (Pd) electrode. Their claims had brought immense attention by scientists, however, subsequent replicative experiments attempts failed and some discredited the initial experiment.