A is the answer for this question
<span>These extra calories are needed by people with HIV because their immune system is constantly fighting off the HIV virus. This is because HIV attempts to evade the infection even as the immune system attempts to eradicate it. The extra calories give the immune cells, which are extra strained, the energy to perform their functions.</span>
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-
I believe the answer to this is Pictograph.
