Question

Viruses possess
A. DNA only
B. Nucleic acid, DNA or RNA
C. Protein only
D. Nucleic acid and protein

Answer 1

The genetic material of most viruses is either RNA or DNA. The nucleic acid may be single-stranded or double-stranded. The entire particle of the infectious virus, called a virion, consists of nucleic acid and an outer protein shell. Only enough RNA or DNA to encode four proteins are found in the simplest viruses.

Complete answer:
A virus is a small infectious agent that replicates only within other organisms' living cells. A virus consists of a genetic material center that can be either DNA or RNA, but not both. A protective coat called a capsid, which is made up of protein, covers the genetic material. Sometimes, the capsid is covered by an extra spikey coat called the envelope. So 'Nucleic acid and protein' is the right response.

Additional information: Both viruses contain either DNA or RNA nucleic acid (but not both) and a protein coat containing nucleic acid. An envelope of fat and protein molecules also encloses certain viruses. In its contagious form, a virus particle is called a virion, outside the cell. Recently, based on the large number of protein folds encoded by viral genomes that are shared with cell genomes, viruses have been declared as living entities. This suggests that from several ancient cells, viruses possibly emerged.
Hence option ‘D. Nucleic acid and protein’ is the correct answer.

Note: In several cases, viruses replicate. For example, viruses are also transmitted from plant to plant by insects that feed on plant sap, such as aphids; and viruses in animals can be transmitted by blood-sucking insects. One transmission mechanism is through disease-bearing species known as vectors.