<u>Answer:</u> The correct answer is Option D.
<u>Explanation:</u>
Atomic mass of an atom is defined as the sum of number of neutrons and number of protons that are present in an atom. It is represented as 'A'.
Atomic number = Number of protons + Number of neutrons
We are given:
Number of protons = 6
Number of neutrons = 6
Number of electrons = 6
Atomic mass = 6 + 6 = 12
Hence, the correct answer is Option D.
They'd observe any new substances or new color, and temp. that is irreversible.
If this helped and you have any other questions, feel free to comment on my wall. Hope this helped.
The answer is protons. Neutrons have no charge and electrons have a negative charge so the positive charge must be protons.