<u>Answer:</u> The atom with 6 protons and 6 neutrons and an atom with 6 protons and 7 neutrons are the isotopes of same element.
<u>Explanation:</u>
Isotopes are defined as the chemical species that belong to the same element but differ in their mass number.
This also means that the chemical species have same number of protons and electrons but different number of neutrons.
Atomic number is defined as the number of protons or electrons that are present in a neutral atom.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
From the given options:
The elements having same number of protons will be the isotopes of same element.
Hence, the atom with 6 protons and 6 neutrons and an atom with 6 protons and 7 neutrons are the isotopes of same element.