Answer:
The four nitrogen bases are Thymine(T), Adenine(A), Cytosine(C), and Guanine(G).
Step-by-step explanation:
In DNA, T, A, C, and G are the four nitrogen bases, these bases are often paired together.
T and A are always paired together, and C and G are always paired together.
You can not make different combinations with these bases.
Or at least from what I learned.
I wish you good luck with my answer! :)