Question

a revolutionary discovery came for louis pasteur, not when he was working tirelessly, but when he went on vacation. pasteur had instructed his assistant to inject chickens with a disease bacteria he was testing. the assistant forgot, however, allowing the bacteria to spoil. when the assistant finally remembered and injected the chickens with the bacteria, they sickened, but didn’t die. instead, they recovered completely and couldn’t be infected again, even with fresh bacteria. pasteur realized that vaccines could be generated artificially, in the laboratory—something that had not been known before this. what generalization about scientific discovery could be based on this passage?
1 the results of a successful experiment are not considered valid until they have been replicated several times.
2 sometimes the unanticipated results of accidents can yield more useful results than carefully planned experiments.
3 lab assistants do a great deal of the work, while lead scientists take credit for any discoveries made.

Explanation:

• Option 1: The passage does not mention replicating experiments for validity, so this is irrelevant.
• Option 2: Pasteur's discovery came from an accident (assistant forgot to inject bacteria on time), leading to unanticipated results (chickens recovered and became immune) that were useful (led to understanding artificial vaccine generation), matching this option.
• Option 3: The passage focuses on the discovery from an accident, not on lab assistants' work vs. scientists' credit, so this is incorrect.

Answer:

1. Sometimes the unanticipated results of accidents can yield more useful results than carefully planned experiments.