A phage is a virus that infects bacterial cells. A phage virus is shown above. What component of the phage virus is indicated by the arrow?
A) the capsid made from protein
B) stored carbohydrates for energy
C) the enzyme reverse transcriptase
D) the nucleic acid (either DNA or RNA)

D) the nucleic acid (either DNA or RNA)

Explanation:

Phages, or bacteriophages are viruses that infect bacteria.They have varying shapes, and sizes, and may contain one of two kinds of nucleic acid; these are RNA and DNA.

The nucleic acids  are made up of nucleotides. These are  genetic storage biomolecules made up of the monomers ribonucleic acid (RNA) deoxyribonucleic acid (DNA).

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.