Example of isotopes are Hydrogen and deuterium.
Hydrogen is 1 proton and 0 neutrons.
Deuterium is 1 proton and 1 neutron
option D. isotopes of the same element.
1) The number of protons is the atomic number of the element. Atomic number is what identifies the element. None two different elements can have the same atomic number (number of protons).
On the other hand, the atoms of an element can differ on the number of neutrons.
Isotopes are atoms of the same element, ergo with the same number of protons, but different number of neutrons.
As per the other choices:
A) ions are charged particles: substances with either excess or defect of electrons.
B) There are several different elements (kind of atoms) in a column of the periodic table, and, of course, being different elements they have different number of protons
C) Two atoms next to each other on the periodic table are different kind of atoms, so they have different number of protons.
The answers are given below;
the answers would be
the first one and the second one