Answer:
Second option.
Explanation:
Nitrogen is the first element of group 15, and its number atomic is 7, so, in its neutral state, it has 7 electrons.
By Linus Pauling diagram (see figure), the electronic distribution will be:
The distribution follows the arrows, from the less energetic subshell for the most energetic one. The subshell <em>s</em> has an only magnetic number, so only one orbital to put electrons. Subshell <em>p</em> has 3 magnetic numbers, so 3 orbitals to put electrons.
To put the electrons, we have to follow Hund's Rule: fulfill the orbitals which only one<em> spin</em>, until all orbitals have this <em>spin</em>, so continue, with the other <em>spin</em>, until finishing the electrons on that subshell. <em>Spin</em> is the rotation of the electron, and it can be +1/2 or -1/2.
So, for subshell 2p, how there are only 3 electrons, all three will be put with the same <em>spin</em> (+1/2, up arrow). If there was one more electron, it would be filled in the first orbital with the <em>spin</em> -1/2, down arrow.