In each option, the table gives the numbers of neutrons, protons and electrons in two atoms, some of which are ions. Which pair of atoms in the table are isotopes of the same element?
- Aneutrons: $20, 20$; protons: $17, 19$; electrons: $20, 20$
- Bneutrons: $28, 28$; protons: $23, 24$; electrons: $23, 24$
- Cneutrons: $34, 36$; protons: $29, 29$; electrons: $29, 28$
- Dneutrons: $40, 42$; protons: $32, 31$; electrons: $32, 32$