Which part of DNA is different compared to RNA?

The correct choice highlights the differences between DNA and RNA in terms of both sugar and nitrogenous bases. DNA contains deoxyribose sugar, while RNA contains ribose sugar. The distinction lies in the structure of the sugars: deoxyribose lacks one oxygen atom that ribose has, which affects the stability and reactivity of the molecules.

Additionally, DNA utilizes thymine as one of its four nitrogenous bases, whereas RNA substitutes thymine with uracil. These structural differences play crucial roles in the functions of DNA and RNA in biological systems. DNA typically serves as the genetic blueprint for an organism, whereas RNA is involved in various roles such as protein synthesis and carrying messages from DNA.

Therefore, the combination of deoxyribose sugar in DNA and thymine as a base, as mentioned in the correct answer, emphasizes the fundamental biochemical distinctions between the two nucleic acids.