Which sequence is an example of radioactive decay

An example of a radioactive decay would be a polonium isotope becoming a lead isotope when the polonium nuclide emits two protons and two neutrons. A radioactive decay is a process that involves an atom that has an unstable nucleus losing energy through emitting radiation in the form of alpha, gamma or beta particles. I don't know if it is right but, don't blame me, blame google

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.

i think it would be 5