Answer : A) nucleons
Protons and neutrons are sometimes collectively called nucleons because they both are inside the nucleus of an atom.
O2 refers to two oxygen atoms bonded together, while 2 O refers to two oxygen atoms that are not bonded to each other. They both have two oxygen atoms, but in O2, the oxygen atoms are bonded, while in 2O, the atoms are not.
Last One.... If Im not Wrong!
Burning of Fossil Fuels, Increase the CO2 And therefore the Green Effect!!