Theres no chart in your question.
Adenine forms two hydrogen bonds with thymine in DNA while three hydrogen bonds are formed between guanine and cytosine.
Thymine and cytosine are pyrimidines because they have a single ring structure. Adenine and guanine are purines because they have a double ring structure.
Answer:
The options to complete the question are
1
2
3
4
The answer is nothing else but 2.
