They have already had it and carrier of it with asymptotic and never knew or if they catch after rains peoples systems are low. In immune systems that is the natural fighter that cross the blood and brain. Barrier if low they can be prone to catching it as well.
But the answers provided im not seeing the real answer as in they put the problem that caused a. Disease in a vaccine only so much of it and add antidote example flu shot . It attacks some people immune system and they get sick because of injecting it into them but the belief is of catching it after I don’t believe I believe either your body can handle it or it does not and rejects it in the blood brain barrier so if recieved then you will get sick after getting the immunization
C. The material for it is super expensive and sometimes fragile, which sucks, but it's true.
So the entire plant and all of its cells receive water
I think the answer is B because it use mechanical power and convert it into electricity
