What is true of the orbitals in the 3d energy level? A. They have higher energy than 2s orbitals.
B. They have lower energy than 4f orbitals.
C. Together, the five 3d orbitals can hold 10 electrons.
D. All of the above are true.

D. All of the above are true.

Explanation:

All the given options in the problem are true.

According to Aufbau's principle, the sublevels with lower energy are filled before those with higher energies.

The order of filling according to their energies is;

1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p

We see that the 3d energy level is lower than 4f but higher than 2s.

Also, the 3d orbital has 5 subshells and each can hold a maximum of two electrons.

This gives a capacity of 10 electrons.

c.

explanation: