Final answer:
The green structures are endospores, stained by malachite green in an endospore staining procedure, which uses heat to help the dye penetrate the endospore's resistant coat.option e is correct.
Step-by-step explanation:
When malachite green is used with heat and then counterstained with safranin during endospore staining, the resulting green structures observed under the microscope are indicative of endospores. Endospore staining is a specialized procedure that involves using a primary stain (malachite green) to penetrate the resistant coat of endospores. This method often incorporates heat to facilitate the staining process.
After the primary stain is applied, the cells are washed, and the counterstain safranin is used, which stains the vegetative cells pink while the endospores remain green. Thus, we can conclude that the green structures in this scenario are the endospores within the bacterial cells.