Which nuclear decay emission has the weakest penetrating power?

1. alpha particle

2. bera particle

3. gamma radiation

4. positron

Alpha particle is the nuclear decay emission that has the weakest penetrating power. The correct option among all the options that are given in the question is the first option or option "1". Gamma is a type of radiation and so can be negated as a particle. Alpha particles have the largest radiation and so the weakest penetrating power.