The set-up can measure comparatively the rate of?

The diagram below is an illustration of an experimental set-up. Study it and answer the question below;

A. evaporation from leaves on a single shoot under different experimental conditions
B. salt uptake by shoots from different plants
C. transpiration of a single shoot of a plant under different experimental conditions
D. water uptake by roots of different plants

Correct Answer:

Option C – transpiration of a single shoot of a plant under different experimental conditions