Atoms are electrically neutral because they have equal numbers of protons positively charged and electrons negatively charged.
Answer:
Option C. The lungs.
Explanation:
Alveolis are the air sacs in the lungs which main function is to get oxygen into your bloodstream and carbon dioxide leaves the blood.
The alveolis are located in the lungs, and it's where the respiratory and circulatory systems meet, for the reasons stated before.
Therefore, the correct option is Option C.
A reason to theory should support the theory , and it can be testified also, otherwise it will not be considered as scientific theory.
So according to above explanation
<span>C. testable . . . supported is the correct answer.</span>