Smallpox is a virus that causes a rash that then turns into painful blisters. the last known case of smallpox was in 1977. what is the best explanation for the eradication of smallpox?

It has been recorded that the last case of small pox occurred in 1977 and since then no other case has been seen.  

According to World Health Organization, small pox has been eradicated. The best justification is the occurrence of ring vaccination. It is basically a strategy to control the occurrence of any small pox case by providing vaccination to people who are at the verge to develop it. Ring vaccination justifies that there is no small pox case occurred since then.

answer;

a. sheep consumption efficiency would be reduced.

explanation;

-trophic efficiency is a measure of how much energy occurs at one level divided by the energy at the level immediately below it . trophic efficiency incorporates three types of efficiency:

-the proportion of available energy that is consumed (consumption efficiency).   it is the proportion of the available biomass that is ingested by consumers.

-the proportion of ingested food that is assimilated (assimilation efficiency).

-the proportion of assimilated food that goes into new consumer biomass (production efficiency).

-in this case, the grasshoppers would affect sheep by reducing the proportion of the available biomass that is ingested by the sheep.