In the diagram, five atoms are shown in a radioactive substance. Each atom emits an $^{{4}}_{{2}}\alpha$-particle. Atom 1 is the first one to emit a particle. Atom 3 is the second one to emit a particle. Which atom will emit the next particle?
- Aatom 2
- Batom 4
- Catom 5
- Dimpossible to tell