Parker is testing 2 different types of ant killer in his yard. He purchases Brand A and Brand B from the home improvement store. He applies Brand A in the front yard on Monday and Brand B in the backyard on Saturday. He then compares the ant hills on Sunday and determines that Brand A is more effective than Brand B. Why is his conclusion not valid? He purchased 2 different types of ant killer.
He did not say how many ant hills he had at the beginning of the test.
He did not wait as long between each treatment of ant killer.
He applied 1 treatment to the front yard and 1 treatment to the backyard.

The reason that the conclusion made by Parker for the quality of each brand of ant killer is given by: Option C: He did not wait as long between each treatment of ant killer.

What is the criteria for comparing quality of two things?

Well this cannot be said for universally, but atleast, both the things in comparison should get equal opportunity (at least in those cases where it is useful to provide them equal opportunities).

For this case, we are provided that:

Parker applied Brand A in frontyard on monday.
Parker applied Brand B in bachward on saturday.
He checked their results on sunday.

He didn't gave enough time to brand B as he gave to brand A(assuming he watched the effects on the upcoming sunday from the date of appliance of the ant killers).

Well there might be differences in front and back yard, but generally this assumption is made that he compared the effects in proportion.

Thus, the reason that the conclusion made by Parker for the quality of each brand of ant killer is given by: Option C: He did not wait as long between each treatment of ant killer.

Learn more about valid conclusions here:

https://brainly.com/question/6669534