Wich is a nitrogen base that is located within an RNA molucule, but NOT within a DNA molecule?

The correct answer is Uracil which is nitrogen base found in RNA.

Explanation:

Uracil is a nitrogenous base which is located within an RNA molecule but not within a DNA molecule.

Uracil, represented by the letters A, G, C and U, is one of the four nucleobases that are found in the nucleic acid of RNA which binds to adenine.

While thymine is present in the DNA and binds to adenine.