Which of the following statements is NOT true about nitrogenous bases?

The statement that guanine pairs with uracil is not true in the context of DNA. In DNA, the pairing of nitrogenous bases follows specific rules, where adenine pairs with thymine and guanine pairs with cytosine. This pairing is fundamental to the structure of DNA, contributing to its double helix formation.

In RNA, however, uracil does replace thymine, but it pairs with adenine instead of guanine. Therefore, while uracil is a nitrogenous base found in RNA, it does not pair with guanine in either DNA or RNA. Understanding these pairing rules is crucial for grasping how genetic information is encoded and transmitted in living organisms.