Biology

A student is testing the effect of different water temperatures on the germination rate of bean seeds. She uses three groups: one group is watered with cold water (5°C), another with room-temperature water (20°C), and the third with warm water (35°C). She ensures that all the seeds receive the same amount of water, are planted in the same type of soil, and are placed in the same environment.

After 10 days, the student observes the following germination rates:

1. Cold water group: 40% germination

2. Room-temperature water group: 80% germination

3. Warm water group: 50% germination

What can the student conclude from this data?