Item 3 Read the excerpt from “Louis Pasteur: Battle with Death.”

He found that by letting this tissue stand for a few days it became weak. When a dog received this weak nerve tissue it became sick, yes. But not so sick that it died. The dog got well. And after that, even if injected with the strongest nerve tissue, the dog did not develop rabies. Its body had built up strength against the disease. The dog was “immune.”

The scientist knew that persons bitten by rabid dogs do not show signs of illness until nearly a month later. If resistance could be built up in these people before they showed signs of the disease, perhaps they might not sicken at all! He worked up a course of treatment. It would take fourteen days.

On the first day a dose of a very weak fourteen-day-old nerve tissue was to be given to a person who had been bitten. This was followed on the second day by a thirteen-day-old dose. And so on, until on the last day strong virus was to be given. During this time the person’s body would be building up resistance. Finally, the victim would have so much resistance that he would not get sick.

How do the details in the excerpt support its main idea?
Correct Answer