Dolphin fins and shark fins: a. are probably built by different genes.
b. are an example of divergence.
c. suggest these two populations could interbreed.
d. are evidence that adaptive evolution is mainly driven by random forces.
e. None of the above is correct.

a. are probably built by different genes.

Explanation:

Although sharks and dolphins are aquatic animals belonging to the vertebrate group, sharks are fish while dolphins are mammals. Sharks belong to the class Chondrichthyes which are fish that have a cartilaginous skeleton. On the other hand, dolphins are mammals (class Mammalia) which are animals mainly characterized by the presence of mammary glands. In consequence, both species are not closely phylogenetically linked, thereby those genes involved in the development of the integumentary system (skin) in both species are expected to be different.

good thing- during decomposition the organic molecules in organic matter are broken down into simpler organic molecules that require further decomposition or into mineralised nutrients

bad thing- it can be harmful in crop productivity