Scientists analyze all results. Scientists use safety precautions. Scientists conduct experiments once. Scientists change at least two variables.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Scientists perform experiments to test hypotheses. How do scientists try to remain objective during experiments?
Possibilities:
- Scientists analyze all results.
- Scientists use safety precautions.
- Scientists conduct experiments once.
- Scientists change at least two variables.

Scientists analyze all results.