Which of the following is not a way that the environment can influence traits? through variation in temperature
through epigenetic factors
the presence of toxins in the environment
expression of the dominant trait

Which of the following is not a way that the environment can influence traits?

the presence of toxins in the environment.

Explanation:

The environment cannot influence traits through the presence of toxins in the environment.  But it can influence human traits or characteristics through other factors, including temperature, epigenetic factors, and expression of the dominant trait.  For example, in an environment where males are expected to be the defenders of their families, the men are usually seen as combatants and somehow aggressive.