Which of the following are purine bases?
(i) Guanine
(ii) Adenine
(iii) Thymine
(iv) Uracil
The answer is the option (i) and (ii). The compounds under purines contain a six membered and a five membered ring with nitrogen infused together to make the chemical structure. Thus, the right options are (i) Guanine and (ii) Adenine