Which statements correctly compare lanthanoids and actinoids?

1. AActinoids show a wider range of oxidation states than lanthanoids
2. BThe $5f$ orbitals extend further from the nucleus than $4f$ orbitals, so they take part in bonding more readily
3. CThe energy gap among $5f$, $6d$ and $7s$ is smaller than among $4f$, $5d$ and $6s$
4. DAll lanthanoids are radioactive, like all actinoids