Question

The main reason that it's important to test only one variable at a time is so that

A. qualitative data can be recorded.
B. scientists can easily tell which variable caused the results.
C. scientists can have many hypotheses tested at once.
D. quantitative data can be recorded.

Answer 1

The main reason that it's important to test only one variable at a time is so that: scientists can easily tell which variable caused the results.

Answer 2

The answer would be B because since the scientist is only testing the variables one at a time they won't confuse it with other data. If they were testing more than one at a time the data could be mixed up and the data would end up being wrong. I hope this helps!