Which of the bonding examples below is NOT possible?
(A) a DNA adenine to a DNA thymine
(B) a DNA adenine to an RNA thymine
(C) a DNA guanine to an RNA cytosine
(D) a DNA adenine to an RNA uracil
(E) a DNA guanine to a DNA cytosine
B is not possible. RNA contains only adenine, cytosine, guanine and Uracil instead of Thymine. The rest are correct because Adenine pairs with either uracil (RNA) or thymine (DNA) and cytosine pairs with Guanine