Final answer:
The quote that best supports the answer in Part A is 'There were sharp pains, and sudden dizziness.'
Step-by-step explanation:
The quote from 'The Masque of the Red Death' that best supports the answer in Part A is: B) There were sharp pains, and sudden dizziness.
This quote describes the symptoms experienced by the victims of the Red Death disease, which include sharp pains and sudden dizziness. The fact that the disease progresses and terminates within half an hour is supported by this quote as it suggests that the symptoms come on rapidly and lead to the death of the individual.