What must differ between the atom of two different elements?

a: protons in the atom
b: electrons in the atom
c: neutrons in the atom
d: protons and neutrons in the nucleus

p? ease with this question.

According to the national health and safety standards: guidelines for out-of-home care, what is the proper adult-to-child ratio for children younger than one year? a. one adult to one child b. one adult to two children c. one adult to three children d. one adult to four children