A strand of DNA reads 5′-GTCT…ATGC-3′, with "…" representing many nucleotides.What is its complement?
A) 3′-GTCT…ATGC-5′
B) 3′-CAGA…TACG-5′
C) 3′-CAGA…UACG-5′
D) 5′-GUCT…AUGC-3′
E) 5′-CAGT…TACG-3′

Question

Quizplus · Accepted Answer

In DNA, adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G). Therefore, to find the complement of the given strand, we must replace each nucleotide with its complementary nucleotide. 
- G pairs with C
- T pairs with A 
- C pairs with G 
- A pairs with T 
Thus, the complement of the given strand is 3′-CAGA…TACG-5′.

A Strand of DNA Reads 5′-GTCT…ATGC-3′, with "…" Representing Many