D. Koch
Hope I helped; please mark brainiest if correct :)
Answer:
Prior exposure to smallpox.
Explanation:
The small pox is the infectious disease caused by the different strains of variola virus. The vaccination for the small pox is available to eradicate the disease.
The milkmaids are already and multiple times have the exposure with the small pox. This develops the memory of the small pox virus infection in the immune cells of the individual and they are less likely on the infection exposure with the small pox.
Thus, the answer is prior exposure to smallpox.
<span>tRNA docks on the A site before being transferred to the polypeptide in elongation.
One mnemonic to remember this is E (exit) site, P (polypeptide) site, and A (acceptor) site to remember the sites in a ribosome.</span>