Baryonic dark matter may occur in non-luminous gas or in Massive Astrophysical Compact Halo Objects, and stars. So therefore it’s D.
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Viruses reproduce within the living cells of the host and use the cellular machinery to synthesize their own genome and other components. To gain entry into cells, they have developed a variety of mechanisms to introduce their genes and proteins into host cells.
I would believe it is the Ozone but since it’s not an option the Ferrel Cell is the westerlies and the polar cell is the polar easterlies. So, I would say go with 4! Hope this helps, goodluck! xoxo.
C. It is made of 11 atoms and 3 elements