The second one changes in the amount of atmospheric gases because it think it might effect everyone including plants and animals because will all breath the same air rather than a mountain building it might affect the animals that like there.
Answer:
Phase III.
Explanation:
Clinical research includes the different steps to test the particular drugs and its use for the medical treatment. Clinical research is divided into four main phases.
The phase III of the clinical research includes the double blinded study and its clinical trial on the patients. This phase determines the drug safety and efficacy. The therapeutic effect of the drug is tested directly in phase III of the clinical trial.
Thus, the answer is phase III.
<span>D. grass they eat and water they drink</span>
