Which of the following is true about the number of subatomic particles of the element Argon (Ar)?
a. It has 18 protons, 18 electrons, and 22 neutrons.
b. It has 18 protons, 18 electrons, and 42 neutrons.
c.It has 22 protons, 22 electrons, and 18 neutrons.
d. It has 22 protons, 22 electrons, and 22 neutrons.