Answer:
Option (1).
Explanation:
DNA (deoxyribo nucleic acid ) is the genetic material present in all the organisms except some viruses. DNA structure follows the Chargaff's rule.
Accoprding to Chargaff's rule, the ratio of purines to pyrimidines in a DNA molecule is equal to 1. The amount of guanine is nearly equal to the amount of cytosine whereas the amount of thymine is nearly equal to the amount of adenine.
Thus, the correct answer is option (1).