The technique to improve internal validity is D) Addition of a control group.
<h3>What is
internal validity?</h3>
Internal validity serves as the study which bring about the establishment of a trustworthy cause-and-effect relationship that can be found in treatment and an outcome.
it should be noted that Internal validity also helps to eliminate alternative explanations , hence, The technique to improve internal validity is D) Addition of a control group.
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COMPLETE QUESTOIN:
Which of the following is a technique to improve internal validity ____________?
A) Experimenter expectancy
B) Participant bias
C) Use of a confederate
D) Addition of a control group
Answer:
cage cultural fish are the species of fish that are commonly cultured in pounds
Answer:
true
Explanation:
to fix a computer problem you have to know what is wrong with it
The number of different combinations of these items that you can make if you choose four (4) toppings is equal to 1.
<h3>How to calculate the combinations of these items.</h3>
In order to determine the combinations of these items that this person can make, we would use this mathematical model known as combination.
Mathematically, combination is calculated by using this mathematical equation:

<u>Where:</u>
- n is the total number of items.
- r is the number of times of choosing items.
<u>Given the following data:</u>
Let us assume you'll choose four (4) toppings.
Substituting the given parameters into the formula, we have;
⁴C₄ = 4/4
⁴C₄ = 1.
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