Which of the following is true about nuclear fusion a) it occurs in the sun
b) a heavy atom is split
c) it can be controlled easily
d) an electron is lost by the atom

 i would assume that it would be (a)

Explanation:

The Sun generates its energy by nuclear fusion

NUCLEAR FISSION is when the heavy atom is split

fusion energy is scientifically feasible. Plasma conditions that are very close to those required in a fusion reactor are now routinely reached in experiments

mass gets lost is nuclear fusion

so (a) is the most accurate

elements make up everything, and they combine to make compounds.

the answer is c