Final answer:
After spore staining, the vegetative cells appear pink due to the application of the counterstain safranin, following a decolorization step that removes the primary stain, malachite green, from the vegetative cells but not from the endospores.
Step-by-step explanation:
The color of the vegetative cell after the spore staining process is pink. During the endospore staining process, the primary stain, malachite green, is used to stain the endospores. Since the endospore coat is resistant to staining, methods such as using heat or a long exposure time are employed to allow the malachite green to penetrate the endospores. After this, a decolorization step is performed, which removes the primary stain from the vegetative cells but not from the endospores. Finally, a counterstain is applied, commonly safranin, which stains the decolorized vegetative cells pink. As a result, when viewed under a microscope, endospores appear green, and vegetative cells appear pink, for example in Bacillus subtilis.