A – Wrong.
11% (100 – 38 – 51) of the people have the VV combination. However, we are not given information about whether people with VV combination can get the disease or not. We cannot assume that those with VV combination will not be susceptible to the disease.
B – Correct.
The second to last statement, which states that, someone with the MV combination recently died of the disease. This means that having one V variant of the gene does not guarantee resistance to vCJD.
C – Wrong.
Eating infected beef does cause vCJD in everyone with the MM combination. This can be inferred from the third to last line.
D – Wrong.
51% have the MV combination. However, it is not entirely certain that all 51% of the people will develop vCJD in the future. There is no statement in the passage, which guarantees that all people with MV combination will develop vCJD.