The study and manipulation of dna on a molecular level is known as
select one:
a. evolution.
b. genomes.
c. biochemistry.
d. molecular genetics.

D. Molecular Genetics

The study and manipulation of DNA on a molecular level is known as molecular genetics because it is done on a "molecular" level and because genetics has to do with the study of genes and DNA.

Hope this helps :)

It's called molecular genetics. :) 

Because it's on a molecular level and DNA contains important genetic information.

They both determine the exact age of rocks.