Darwin's The Descent of Man differed from On the Origin of Species in that:

a. It was based on close observation of one particular species of tortoise.
b. It was less well-written and received poorly by the reading public.
c. It dealt with the subject of human evolution.
d. It was published before Darwin had become a familiar author.

c. It dealt with the subject of human evolution.

Explanation:

the awnser is d i think

what have scientists found to be the most efficient and effective way to insert new sequences into an individual? a-scientists have created genetically altered foods that release dna during digestion. b-scientists use viruses to insert specific gene sequences. c-scientists irradiate genes so that they can be absorbed through the skin.