The molecular evolution studies of sodium channels in puffer fish is used primarily to produce new molecules by in vitro evolution. save puffer fish from extinction. study protein function. determine the evolutionary history of gene families. combat disease.

The most probable answers to this question are C. study protein function. and E. combat disease.
This study has been done as a study for protein function. Puffer fish carry tetrodotoxin (TTX) which can block sodium channels, and puffer fish has developed resistance for it. Scientists have performed this study to learn about how the sodium channels work and find out more about the diseases caused by mutation in channel genes.

Ithink the answer is d.