Avirus's dna or rna is surrounded by a(n)
a) protein coat.
b) nuclear membrane.
c) tail.
d) endospore.

The answer to this question is most likely A) Protein coat.

To know this, we must know that a virus is a single-celled organism AND classified as prokaryotic (meaning it has no nucleus like Eukaryotic cells do). 

A nuclear membrane is a covering that we have around every single eukaryotic cell in our body (also known as a cell membrane), NOT prokaryotic cells.

A tail (or flagellum) is located on the side of some cells in our body and most bacterial cells.

An endospore is a resistant, asexual spore that develops in a bacterial cell.

The only choice that would make even the slightest sense is A) protein coat.

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