Final answer:
Nitrogen, with an atomic number of seven, has seven electrons which are arranged in two electron shells. The first shell is filled with two electrons and the second shell has the remaining five electrons.
Step-by-step explanation:
The atomic number of an element corresponds to the number of protons and, in a neutral atom, the number of electrons it has. Nitrogen has an atomic number of seven, indicating it has seven electrons. In the atomic structure, electrons are arranged in electron shells surrounding the nucleus. The first shell can hold a maximum of two electrons, and the second can hold up to eight electrons.
Since Nitrogen has more than two electrons, the first shell will be filled with two electrons, and the remaining five will be in the second shell. Therefore, Nitrogen will have two electron shells.
The correct answer to the question is: b. two