Why is it important to preserve farmland?
farmland provides an important oxygen source for urban areas.
farmland moderates the temperature of urban areas.
farmland provides crops and fruits to support urban and rural populations.
all of the above

Ascience research group is testing a new type of plant food. one trial is conducted in a controlled experiment. the data from the trial show that the plant that received the new food grew faster than the control plant. the group announces that the new plant food makes plants grow faster. what is the main weakness in this scientific claim?