Answer:
C. <em>Clostridium</em> and <em>Bacillus</em>.
Explanation:
<em>Bacillus </em>and <em>Clostridium</em> are the gram-positive bacteria and form endospores. Endospores are the resistant dormant structures formed by some gram-positive bacteria.
These bacteria form the endospores within their vegetative cells. The endospores are highly resistant to environmental stress conditions and make these bacterial genera the dangerous pathogens.
Elements [or radicals] with valency one are monovalent, those with valency two are divalent, and those with valency three are trivalent.
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What is the Valency of an Element / Radical?
Valency Divalent [2]
Element / Radical Oxide [Oxygen]
Symbol O
Ion O2-
Consume a low carbohydrate diet and high protein, avoid fasting