Step 1: Understanding the Concept:
The question requires matching different types of ecosystems with a characteristic producer (plant) found within them.
Step 3: Detailed Explanation:
Let's match each ecosystem with its producer:
\[\begin{array}{rl} \bullet & \text{(A) Deserts: Capparis (the caper bush) is a genus of plants that are often xerophytic, meaning they are adapted to survive in dry conditions like deserts. So, (A) matches (II).} \\ \bullet & \text{(B) Grasslands: Cymbopogon (lemongrass) is a genus of grasses, which are the dominant producers in grassland ecosystems. So, (B) matches (I).} \\ \bullet & \text{(C) Ponds and Lakes: Hydrilla is a well-known aquatic plant (a hydrophyte) that often grows submerged in freshwater bodies like ponds and lakes. So, (C) matches (III).} \\ \bullet & \text{(D) Moist deciduous forests: Tectona (Teak) is a large deciduous tree that is a dominant and economically important species in the moist deciduous forests of India and Southeast Asia. So, (D) matches (IV).} \\ \end{array}\]
The correct set of matches is A-II, B-I, C-III, D-IV.
Step 4: Final Answer:
The correct matching option is (A) - (II), (B) - (I), (C) - (III), (D) - (IV).