What radionuclide is known for emitting beta particles that can penetrate container walls and skin?

Phosphorus-32 is known for emitting beta particles that possess a significant ability to penetrate materials, including container walls and even skin. Beta particles are high-energy, high-speed electrons or positrons emitted by certain types of radionuclides when they decay.

In the case of Phosphorus-32, the beta particles have enough energy to penetrate skin, which raises concerns for radiation safety when handling this radionuclide. This makes proper shielding and handling procedures essential to minimize exposure.

While other options may emit radiation, their properties regarding beta particle emission and penetration vary. This is why Phosphorus-32 is specifically noted for its penetrating capabilities concerning beta radiation, making it the correct choice in this context.