This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General, Subject name: Microbiology
In negative staining - 
Select and explain. 
A. The structure to be demonstrated is stained, B. The structure to be demonstrated is not stained, C. The background is not stained, D. The background and structure are stained
B: The structure to be demonstrated is not stained
Answer: B: The structure to be demonstrated is not stained 
Explanation: Negative staining is an established method, often used in diagnostic microscopy, for contrasting a thin specimen with an optically opaque fluid. In this technique, the background is stained, leaving the actual specimen untouched, and thus visible. This contrasts with 'positive staining', in which the actual specimen is stained.