Which statement concerning $\alpha$-particles and $\beta$-particles is correct?
- A$\alpha$-particles are less ionising than $\beta$-particles.
- B$\alpha$-particles are more penetrating than $\beta$-particles.
- C$\alpha$-particles have greater mass than $\beta$-particles.
- D$\alpha$-particles have the same charge as $\beta$-particles.