I would think the public waters source due to bacteria contamination
I believe the bone system that red marrow belongs to is D. Skeletal system.
Answer:
The answer is number two extinction happened, this was the time dinosaurs went extinct ebcause lack of sun because oh how much dirt was blown into the earth atmosphere becuase of the asteriod, third option is talking about big bang theroy so that dosnt apply!
Explanation:
<span>The scientific community ensure that all work done and shared is purely objective and based on solid facts and complete experimental procedure. Therefore, the scientific method is adopted to avoid bias in experiments. A bias would cause results to be skewed to fit the researchers' personal views, making the finding unreliable.</span>