CV-1 complex is formed during Gram staining in:

Explanation

CV-1 complex is formed during Gram staining in Gram-positive bacteria. The Gram stain is a method of differentiating between two main types of bacteria: gram-positive and gram-negative. The Gram stain is based on the different chemical compositions of the cell walls of these two types of bacteria. During the Gram stain, the bacteria are first treated with crystal violet, which stains all bacteria purple. Then, they are treated with iodine, which forms a complex with the crystal violet. This complex is called the CV-1 complex. Gram-positive bacteria retain the CV-1 complex because their thick cell walls prevent the decolorizer from penetrating the cell.