Dr Bloomin Wants to Investigate the Impact of Talking to Plants

Multiple Choice

Dr. Bloomin wants to investigate the impact of talking to plants on their growth. He decides to talk to a group of 40 tulips each day for six weeks. A second group is not talked to at all. After six weeks he discovers that the tulips he talked to are five centimetres taller than the tulips not talked to. In this example, the independent variable is:

A) the group of tulips spoken to
B) whether the tulips are spoken to
C) the height of the tulips
D) the group of tulips not spoken to