The last statement is correct
They both have seven protons in the nucleus.
it's wrong because they have six protons in the nuclear
They both have the same mass number.
it's wrong because Carbon-12 has mass number 12 but Carbon-13 has mass number 13
They both have seven neutrons in the nucleus.
it's wrong because Carbon-12 has six in the nucleus but Carbon-13 has seven in the nucleus
They both have the same atomic number.
It's true. They have the atomic number - 6