A team of scientists conducted an experiment to determine the effect of different watering frequencies on the growth of basil plants. They divided the plants into three groups based on watering frequency:Group A: Watered once every dayGroup B: Watered every other dayGroup C: Watered once a weekThe plants were placed in identical containers with the same type of soil, and they were kept in a controlled environment with constant temperature and light. The height of each plant was measured at the end of 6 weeks, and the average heights are presented in the table below.GroupWatering FrequencyAverage Plant Height (cm)AEvery day25BEvery other day20COnce a week10After the experiment, some scientists noted that the plants in Group A showed signs of root rot, while Group C plants appeared dry and withered.Question:Which of the following is a potential methodological flaw in this experiment that could affect the interpretation of the results?