answer is oxygen .
oxygen is an exception in octet rule
Answer: Quora. What is the charge of the ion typically formed by bromine and how is it calculated? Bromine has seven valence electrons (found with a quick google search or the fact that it's a halogen or the fact that it's in group 17 or 7A) but wants eight, just like all atoms not in groups 1 and 2.
Explanation:
Answer: D) nuclear fusion because an atomic nuclei combine to form a heavier nucleus
Explanation:
Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.
Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

As in the given reaction a heavier nuclei helium is being formed from combination of deuterium and tritium, this is a nuclear fusion reaction.
To covert from moles to atoms times the number of moles by Avogadro's Number (6.022×10²³)
4.0 × 6.022×10²³ = 2.4088×10^24