Final answer:
The stable isotopes of nitrogen are 14N and 15N, meaning option A) is correct. These isotopes have a balanced number of protons and neutrons which contributes to their stability.
Step-by-step explanation:
The stable isotopes of nitrogen are 14N and 15N. The isotope 14N has seven protons and seven neutrons, while 15N has seven protons and eight neutrons. Both of these isotopes are stable and do not undergo radioactive decay under normal conditions, making A) 14N and 15N the correct answer.
Just as in the case of carbon, where Carbon-12 (12C) is the most common and stable nucleus with a 1:1 neutron to proton ratio, and Carbon-14 (14C) is unstable and rarer, nitrogen has its stable isotopes which follow a similar principle in terms of stability.