Step-by-step explanation:
The orbital diagram that represents the ground state of Be would have two electrons in the 1s orbital and two electrons in the 2s orbital, with the following configuration:
1s↑↓ 2s↑↓
The "1s" and "2s" notations refer to the energy levels of the orbitals, with "1s" being the lowest-energy level and "2s" being the next highest. The arrows indicate the spin of each electron; up arrows represent "spin up" electrons, while down arrows represent "spin down" electrons.
It's worth noting that the Aufbau principle (which states that electrons fill the lowest-energy orbitals first) and the Pauli exclusion principle (which states that no two electrons can have the same set of quantum numbers) are both reflected in this orbital diagram for the ground state of Be.