16. An appropriate control for his experiment would be
Answer: C
A fern in a pot of soil with no fertilizer
Using a fern in a pot of soil with no fertilizer serves as an appropriate control for the experiment, allowing the student to compare the growth of ferns with and without the application of the miracle fertilizer.
A) a fern in a pot of soil with a minimal amount of fertilizer
While this option could provide some insight into the effects of a low dose of fertilizer, it does not serve as a true control. A minimal amount of fertilizer may still influence the growth of the fern, making it difficult to determine the specific effects of the miracle fertilizer compared to no fertilizer at all.
B) a fern in a pot of soil with a large amount of fertilizer
This choice would not be an appropriate control because it introduces a variable that could significantly alter the growth rate of the fern. The purpose of a control is to isolate the effect of the variable being tested—in this case, the miracle fertilizer—making this option unsuitable.
C) a fern in a pot of soil with no fertilizer
This option effectively isolates the variable of interest. By having a fern grow without any fertilizer, the student can clearly measure the growth differences when comparing it to ferns treated with the miracle fertilizer, thus validating or refuting the hypothesis.
D) a fern in a pot with nothing but fertilizer
This option does not provide a suitable control as it lacks soil, which is necessary for the fern's growth. Without soil, the fern may not grow at all, rendering the results meaningless in the context of the experiment aimed at assessing fertilizer effects.
Conclusion
The correct choice, a fern in a pot of soil with no fertilizer, allows for a direct comparison to evaluate the effects of the miracle fertilizer on fern growth. All other options either introduce additional variables or fail to provide the necessary conditions for the fern to grow, thus undermining the integrity of the experiment. Using a proper control is crucial in scientific experimentation to draw valid conclusions.