What is analyzed using a "Northern Blot"?

A Northern Blot is a molecular biology technique specifically used for the detection and analysis of RNA. The procedure involves the separation of RNA samples by gel electrophoresis, followed by transfer to a membrane and hybridization with a labeled probe that is complementary to the target RNA sequence. This allows for the identification of specific RNA molecules within a complex mixture, enabling researchers to study gene expression levels and RNA processing.

In contrast, the other options pertain to different techniques: DNA analysis is typically performed using Southern Blotting, which targets DNA fragments, while protein analysis is done with Western Blotting. Thus, the specificity of the Northern Blot for RNA underlines why RNA is the correct answer in this context.