Ecological pyramids are of
I. three types (age pyramids, energy pyramids and biomass pyramids).
II. four types (age pyramids, energy pyramids, number pyramids and biomass pyramids).
III. five types ((age pyramids, energy pyramids, number pyramids, tropical pyramids and biomass pyramids).
Select the statements with the correct option.

Options

A. I, Il and II
B. I and II
C. I only
D. None are correct

Answer

To solve the question regarding the types of ecological pyramids, we will analyze each statement provided and determine which one is correct.

**Step 1: Understand the Types of Ecological Pyramids**
Ecological pyramids are graphical representations that show the relationship between different trophic levels in an ecosystem. The three main types of ecological pyramids are:
1. **Pyramid of Number**: This shows the number of individual organisms at each trophic level.
2. **Pyramid of Biomass**: This represents the total mass of living matter at each trophic level.
3. **Pyramid of Energy**: This illustrates the flow of energy through different trophic levels.

**Step 2: Analyze the Statements**
Now, let's evaluate the statements provided in the question:
- **Statement I**: "three types (age pyramids, energy pyramids and biomass pyramids)" - This statement is incorrect because it mentions "age pyramids," which is not a recognized type of ecological pyramid.

- **Statement II**: "four types (age pyramids, energy pyramids, number pyramids and biomass pyramids)" - This statement is also incorrect for the same reason as Statement I; it includes "age pyramids."

- **Statement III**: "five types (age pyramids, energy pyramids, number pyramids, tropical pyramids and biomass pyramids)" - This statement is incorrect as well, as it includes "age pyramids" and "tropical pyramids," which are not standard types of ecological pyramids.

**Step 3: Conclusion**
Since all three statements contain inaccuracies regarding the types of ecological pyramids, we conclude that none of the statements are correct. The correct classification of ecological pyramids is limited to three types: Pyramid of Number, Pyramid of Biomass, and Pyramid of Energy.

**Final Answer**: None of the statements are correct.

---