Which of the following correctly identifies all the components of a viral nucleocapsid?

• A. Envelope and capsid
• B. Nucleic acid, capsid, and envelope
• C. Capsid and glycoprotein spikes
• D. Nucleic acid and capsid

Answer: (D)

Verified step by step guidance

1. Understand the term 'nucleocapsid': it refers specifically to the combination of the viral nucleic acid (genetic material) and the protein coat called the capsid that surrounds and protects this nucleic acid.
2. Recognize that the envelope is a separate structure from the nucleocapsid; it is a lipid membrane derived from the host cell and surrounds the nucleocapsid in some viruses but is not part of the nucleocapsid itself.
3. Identify that glycoprotein spikes are proteins embedded in the viral envelope used for attachment to host cells, and they are not components of the nucleocapsid.
4. Therefore, the nucleocapsid consists only of the nucleic acid and the capsid, excluding the envelope and glycoprotein spikes.
5. Conclude that the correct identification of all components of a viral nucleocapsid is 'nucleic acid and capsid' because these two together form the core structure of the virus.