In an appropriate design experiment, a scientist is able to test the effect of?

This question is incomplete as it lacks options, the options are:

A) a single variable

B) multiple variables

C) the hypothesis

D) scientific observations

The answer is A

Explanation:

An experiment is conducted to solve a particular problem or find answers to a given scientific question. In an experiment, which usually consists of variables, only A SINGLE VARIABLE is tested at once.

This means that the effect of a variable called INDEPENDENT VARIABLE is tested at a time. The independent variable is the variable that is changed or manipulated in an experiment. This means that only a SINGLE VARIABLE can be changed at at time in an an appropriate design experiment.

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