A monoclonal (antibody specific for a given epitope of an antigen) IgG antibody (M) was produced in the laboratory that binds to a surface protein $(\mathrm{P})$ of a virus (V1) and neutralizes $100 \%$ of V 1 . It was observed that M is also effective in neutralizing other viruses V2, V3 and V4 at 40\%,90\% and 32\% efficiency as compared to V1. If there are no other confounding factors, then the most accurate inference is

• A

  V1, V2, V3, and V4 have identical surface protein P.
• B

  the genome of V1 and V3 has to be $90 \%$ identical for the observed binding efficiency.
• C

  the sequence of P is more similar in V2 and V4 than in V1 and V2
• Correct answer
  D

  a segment of sequence in P is highly conserved in V1 and V3 whereas the same segment is less conserved in V2 and V4.

Hence, the correct answer is option: 'D'.