Answer:
The correct answer is option D, that is, all of the above.
Step-by-step explanation:
While performing an experiment to find the effects of the environment on a life form there is a need to consider a lot of factors as many factors in tandem can affect the species in a mentioned scenario. While testing some of the variables would not be seemed obvious at first instance, therefore, in the first look or test, the outcomes are generally inconclusive. At the same time, there is a need for each of the variables to be tested carefully, and also some of the variables may consume more time in order to sound conclusive.