Which of the following statements is true? Only the first principle energy level can have s orbitals. Every principle energy level can have only one s orbital. Every principle energy level can have one s orbital, 3 p orbitals, 5 d orbitals, and 7 f orbitals. The fourth principle energy level is the first energy level that has d orbitals. Every principle energy level can have an s orbital and 3 p orbitals.

Every principle energy level can have only one s orbital.

Explanation:

For many-electron atoms we use the Pauli exclusion principle to determine electron  configurations. This principle states that no two electrons in an atom can have the  same set of four quantum numbers. If two electrons in an atom should have the same  Principal, Angular Momentum and Magnetic quantum numbers' values (that is, these two electrons are in the same atomic orbital), then  they must have different values of Electron Spin Quantum Number. In other words, only two electrons may occupy  the same atomic orbital, and these electrons must have opposite spins.

B

Explanation:

Every principle energy level can have only one s orbital.

Aufbau principle works in the following formula:

1s2, 2s2 2p6, 3s2 3p6, 4s2 3d10 4p6, and so on.