Your class is competing with another class to determine who has the best plant color. Your class decides to test a couple of solutions to determine which would be best for overall plant color before competing. Starting with four sets of four plants, the class decides to water each set with a different solution. They water them once a week with 200ml of the following solutions: water, diet soda, 1% bleach solution, and a 1% salt solution. All plants are placed in the window that receives the recommended amount of light. After a month of testing, your class notices that only two plants are alive, but one of those two does not look healthy. Based on these results, which of the following would be a good hypothesis to design the next experiment around?
A. Plants need more than 200 mL of liquid per week.
B. Salt has no impact on plant health.
C. Salt contains useful nutrients for plants.
D. A combination of the solutions tested will produce healthier plants.
Since only 2 out of the initial 16 plants survived the whole month, it would be reasonable to test variables that were shared by all the plants. As such, the amount of liquid the plants need would be a good follow-up experiment. It is not specified as to which plants survived, so there is not enough information to think that testing the impact of salt is warranted. Additionally, since almost all the plants died, it is not reasonable to assume that a combination of the solutions would have an impact.
Therefore, the Correct Answer is A.