Bacillus megaterium color after counterstain added

Explanation:

The Bacillus megaterium, following the counterstain process, would typically be Purple. This is due to the fact that B. megaterium is a gram-positive bacteria. The process of Gram staining involves staining the cells with a purple crystal violet dye. The cells are then treated with a mordant and subjected to a decolorizer, which usually keeps the gram-positive bacteria purple and turns gram-negative bacteria colorless. Lastly, a counterstain like safranin is applied. Gram-negative bacteria which were decolorized, now turn pink, but the gram-positive bacteria retain their purple color due to their thicker peptidoglycan wall which resists the decolorization. Also worth noting, in certain cases of endospore staining methodologies such as the Schaeffer-Fulton method, B. megaterium might appear green if it's producing endospores. Malachite green is used as primary stain and safranin is used as counterstain. However, if just considering a common counterstain like safranin, it won't significantly alter the color of gram-positive bacteria like Bacillus megaterium.