Which types of orbitals are found in the principal energy level n = 3?
a. s, d

b. s, p, d

c. s, p

d. s, p, f

e. s, d, f

The principal energy level at n=3 contains s,p,d orbitals in their valence shell.

Option(b);

Explanation:

"Principal energy level" is used to locate the no of electrons in each orbital to its atomic nucleus. These energy levels are denoted by the "principal quantum number" n.

There are four energy level of orbits available in this system. And the following shows different level of orbits and the no of electrons for each value of n