Exposure to pesticides or industrial chemicals
a. always has immediate and apparent side effects
b. decreases the risk of developing genetically influenced diseases
c. increases the risk of developing genetically influenced diseases
d. has no effect on the risk of contracting genetically influenced diseases

Exposure to pesticides or industrial chemicals c. increases the risk of developing genetically influenced diseases. Though these chemicals may have some short term effects, they have more dangerous long term effects such as the development of diseases which could be passed on to future generations. It is best to avoid chronic exposure to such chemicals.

Explanation:

Coniferous means 'cone bearing,' meaning these trees don't lose their leaves every year. Deciduous means 'falling off' so those trees lose their leaves every year. I would assume the difference is that coniferous forests don't lose their leaves every year while deciduous forests do.