In the structure of DNA, which of the following statements is true?

A. The double helix is held together by covalent bonds
B. The nucleotide is made up of ribose, phosphate, and an organic nitrogen compound
C. Guanine is the opposite of cytosine
D. Adenine is the opposite of cytosine

Correct Answer: Option C

C. Guanine is the opposite of cytosine