Which quantity is directly related to the temperature of a substance?

a.) average kinetic energy of the particles in the substance
b.) average size of the particles in the substance
c.) composition of the substance
d.) ph of the substance

even if you can't , for taking the time to look at my question and see if you can solve it. : )

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

explanation:

as the height from which the ruler was dropped increased, the speed of the ruler at ryan's hand increased.