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What are the components of RNA molecules?

  1. Ribose sugar, uracil, adenine, and cytosine

  2. Deoxyribose sugar, thymine, adenine, and guanine

  3. Ribose sugar, uracil, guanine, and thymine

  4. Ribose sugar, uracil, adenine, and guanine

The correct answer is: Ribose sugar, uracil, adenine, and guanine

The correct choice emphasizes the essential components of RNA molecules, which are ribose sugar, uracil, adenine, and guanine. RNA (ribonucleic acid) is distinguished from DNA (deoxyribonucleic acid) primarily by its sugar and nitrogenous base composition. Instead of the deoxyribose found in DNA, RNA contains ribose. Additionally, while DNA uses thymine as one of its bases, RNA substitutes uracil in place of thymine. The presence of adenine and guanine, which are purines, further confirms this composition. The alternative options incorrectly incorporate components associated with DNA or include incorrect bases. For instance, deoxyribose and thymine are not part of RNA, which clarifies why those selections do not represent the components of RNA molecules accurately. Overall, the selection correctly identifies all the necessary elements that make up RNA.