Concept:Tap root systems belong to dicotyledonous plants, while fibrous root systems belong to monocotyledonous plants.
Explanation:Diagram I shows a tap root system, having one main root with smaller lateral branches.
This type of root is typical of the class Dicotyledoneae.
Diagram II shows a fibrous root system, consisting of many thin roots of similar size.
This type of root is typical of the class Monocotyledoneae.
Therefore, the diagrams represent Dicotyledoneae and Monocotyledoneae respectively.
Answer:A. Dicotyledoneae and Monocotyledoneae
