they are part of the instructions. they are used to test a hypothesis. they are required to make a hypothesis. they keep you safe during an investigation.
I gave my students this multiple choice question: Observation and measurement are important to scientific investigations because

Only one answer is correct among these 4 choices:
- they are part of the instructions.
- they are used to test a hypothesis.
- they are required to make a hypothesis.
- they keep you safe during an investigation.

Could you tell me which one is correct?

they are used to test a hypothesis.