If the dogs are different breeds, their activity levels could be different because of their breed and not the caffeine. The correct option is A.
<h3>Reliability of experiments</h3>
In order for the outcomes of scientific experiments to be reliable, constant variables should be kept constant.
In the illustrated experiments, the breed and age of the experimental dogs have to be the same. It is one of the variables that have to be kept constant throughout the experiment.
If the dogs are different breeds, their activity levels could be different because of their breed and not the caffeine. The same thing is applicable to different ages.
Thus, evaluating this variable and doing right by it will ensure reliability.
More on the reliability of results can be found here: brainly.com/question/1873979
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Answer:
The red blood cells will shrink in size when water diffuses out of them.
Answer: Covalent bonds are a convenient way of describing the way that a few negatively charged electrons can fix their average location so as to hold two positively charged nuclei together. Chemists know about covalent bonds, electrons do not. All electrons are constantly in very fast motion, they are all indistinguishable from one another, and we have to think in terms not of the position of each electron specifically, but of the average distribution of electrons in a molecule. "Bonds" and "localized electrons" are a convenient fictional calculus and accounting system that allows chemists to work out the properties of molecules and the mechanisms of chemical reactions.
Think of a baseball team made up of nine identical siblings, who constantly and rapidly change fielding positions. You can still describe the team as having a short stop or a second base man, even though you cannot identify an individual person with any role.
Explanation: