The base sequence ACTGAC A) could occur in both DNA and RNA. B) could occur in DNA but not in RNA. C) could occur in RNA but not in DNA. D) could occur in neither DNA nor RNA.
The answer is B. We can see in the sequence there are four types of base: A, T, G and C. For A, G and C, they can appear in both DNA and RNA. But for T, it can only occur in DNA, when in RNA, it is U.