In this task, you are given a question containing a blank (_) and two options. You should pick the best option to answer the question. Please answer with "A" or "B".

[EX Q]: Nick asked Christopher how to focus a camera, since _ had never been able to get the hang of that. (A) Nick (B) Christopher
[EX A]: A

[EX Q]: Sarah is overweight and has high cholesterol unlike Jessica who works out so _ is healthy. (A) Sarah (B) Jessica
[EX A]: B

[EX Q]: The lungs reacted badly to the infection, while the kidneys were resilient against it.  The _ were insufficiently tolerant to the virus. (A) lungs (B) kidneys
[EX A]:
A