Which type of the following pyramids are never inverted ?

Options

A. pyramid of energy
B. pyramid of biomass
C. pyramid of number
D. pyramid of dry biomass

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which type of pyramid in an ecosystem is never inverted. Inverted means that the base of the pyramid is at the top, which is not the usual structure of a pyramid.

2. **Types of Pyramids**: There are three main types of pyramids in an ecosystem:
- Pyramid of Energy
- Pyramid of Biomass
- Pyramid of Numbers

3. **Pyramid of Energy**: This pyramid represents the flow of energy through different trophic levels in a food chain. It is always upright because energy decreases as you move up the trophic levels due to energy loss (mainly as heat) at each level.

4. **Pyramid of Biomass**: This pyramid shows the total mass of living matter at each trophic level. It can sometimes be inverted, especially in aquatic ecosystems where the biomass of producers (like phytoplankton) can be less than that of primary consumers (like zooplankton).

5. **Pyramid of Numbers**: This pyramid represents the number of individual organisms at each trophic level. It can also be inverted, particularly in cases where a single producer supports many consumers.

6. **Conclusion**: The only pyramid that is never inverted is the **Pyramid of Energy**. Therefore, the correct answer to the question is the Pyramid of Energy.

### Final Answer:
The type of pyramid that is never inverted is the **Pyramid of Energy**.

---