Here we have to choose the element which has 1s²2s²2p⁴ electronic configuration.
oxygen has the electronic configuration 1s²2s²2p⁴
The electronic configuration of the given elements are shown below:
nitrogen (N): 1s²2s²2p³
oxygen (O): 1s²2s²2p⁴
phosphorous (P): 1s²2s²2p⁶3s²3p³
Sulfur (S): 1s²2s²2p⁶3s²3p⁴
Thus oxygen has the electronic configuration 1s²2s²2p⁴