Which element is nuclear fusion least likely to produce? hydrogen, which has an approximate mass of 1
chlorine, which has an approximate mass of 35
argon, which has an approximate mass of 39
silicon, which has an approximate mass of 28

A. hydrogen, which has an approximate mass of 1

(Photo for proof at the bottom.)

Fusion is the process of two nuclei joining together to form a bigger, more stable nucleus.

Hydrogen being produced from this process is not possible, because a hydrogen's nucleus only consists of 1 proton. 1 proton is the smallest possible nucleus. Combining 2 of the smallest possible nuclei will produce helium, which has 2 protons.

Here's a photo of Edge, good luck.