Which isolated gaseous atom has a total of five electrons occupying spherically shaped orbitals?

A) sodium b) potassium c) boron d) flourine

Let's find the electron configuration of each atom

Atom atomic number electron configuration

Bo 5 1s2 2s2 2p

F 9 1s2 2s2 2p5

Na 11 1s2 s2 2p6 3s

K 19 1s2 2s2 2p6 3s2 3p6 4s

The spherically shaped orbitals are the s orbitals.

You can se in the table that I wrote above that sodium has 2 electrons at 1s, 2 electrons at 2s and 1 electron at 3s orbitals, that is a total of five electrons at s (spherically shaped orbtials).

So the answer is the option A) sodium.