Answer:
nitrogen, carbon
Step-by-step explanation:
DNA nucleotide consists of a phosphate group, deoxyribose sugar and one of the 4 possible bases- adenine, guanine, cytosine and thymine.
The elements that are found in four of the bases are carbon, nitrogen and hydrogen.
Base pairing occurs between a purine and a pyrimidine. Purines are fused double ring structures and can be adenine or guanine, while pyrimidines are single ring structures and can be cytosine and thymine in the case of DNA.