Answer:
E) Both Bacillus and Clostridium.
Step-by-step explanation:
Bacterial endospores production is part of its survival mechanism. Bacteria produces these highly resistant spores that lies dormant in vegetative state, used during unfavourable and stressful environmental conditions. They are produced by gram positive bacteria such as Bacillus and Clostridium, and can lay dormant for years. Endospores are non-reproductive structures resistant to radiations, starvation and chemical disinfectants.