Which of the following procedures is an appropriate negative control for testing the hypothesis that air contains bread mold spores? A. Seal slices of bread in a container to minimize air contact.

B. Place slices of bread in a refrigerated environment.

C. Add ingredients to the bread recipe that will slow mold growth.

D. Expose a different mold-supporting medium to air.

I nedd help!!!

If you do A and the bread gets moldy with no air, then the mold spores probably did not come from the air.

To determine the appropriate negative control for testing the hypothesis that air contains bread mold spores, let's first understand what a negative control is. In scientific experiments, a negative control is a control group that is set up without the hypothesized factor being tested. It serves as a baseline to compare the experimental group with, helping to ensure that any observed effects can be attributed to the factor being tested.

In this case, the hypothesis is that air contains bread mold spores. To set up an appropriate negative control, we need to remove or minimize the factor being tested, which is the presence of mold spores in the air.

Option A suggests sealing slices of bread in a container to minimize air contact. This would prevent fresh air from reaching the bread, potentially minimizing the exposure to any mold spores present in the air. It is a suitable negative control as it aims to block the factor being tested.

Option B suggests placing slices of bread in a refrigerated environment. While refrigeration may slow down mold growth, it does not directly address the presence of mold spores in the air. Therefore, option B is not an appropriate negative control for this hypothesis.

Option C suggests adding ingredients to the bread recipe that will slow mold growth. This option is not a negative control as it introduces changes to the bread itself, rather than addressing the presence of mold spores in the air.

Option D suggests exposing a different mold-supporting medium to air. This option would serve as a positive control rather than a negative control as it would actually test whether the air contains mold spores on a different medium, rather than testing for the absence of mold spores on bread slices.

So, based on the explanations provided, option A is the appropriate negative control for testing the hypothesis that air contains bread mold spores.