In negative staining -: (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
Answer is B. 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.