I think it is rising sea level
Answer:
Protons are found in the nucleus of the atom. This is a tiny, dense region at the center of the atom. Protons have a positive electrical charge of one (+1) and a mass of 1 atomic mass unit (amu), which is about 1.67×10−27 kilograms.6
Explanation:
The answer is D: test possible choices and then avoid ones that are not desirable.