Read the given statements each with one, two or three blanks and select the option that correctly fills any four of these.
(i) An ecological pyramid of numbers is upright in ____P____ ecosystem and inverted in ____Q_____ food chain.
(ii) Pyramid of biomass is upright in ____R____ and inverted in ____S____ ecosystem.
(iii) Gases like `CO_2` allow the ___T____ wave heat radiations of sun to reach the earth's surface but do not allow the ____U____ wave heat radiations reemitted by earth to escape, thereby causing ____V_____ flux.
(iv) Large amount of ____W____ is added to the atmosphere by marshes, paddy fields and biogas plants.

Options

A. P-Grassland, Q-Aquatic, T-Long, W-Sulphur dioxide
B. Q-Parasitic, S-Pond, U-Long, W-Methane
C. Q-Detritus, R-Pond, V-Greenhouse, W-Chlorofluorocarbon
D. P-Parasitic, T-Short, U-Long, W-Carbon monoxide

Answer

To solve the question, we need to fill in the blanks with the correct terms based on our understanding of ecological pyramids, biomass, greenhouse gases, and their effects on the environment. Let's go through each statement step by step.

### Step-by-Step Solution:

1. **Statement (i)**: "An ecological pyramid of numbers is upright in ____P____ ecosystem and inverted in ____Q_____ food chain."
- **P**: The ecological pyramid of numbers is typically upright in a **grassland ecosystem**. This is because there are more producers (plants) than consumers (herbivores and carnivores).
- **Q**: It is inverted in a **parasitic food chain**. In this case, there are more parasites than the hosts they depend on, leading to an inverted pyramid.

2. **Statement (ii)**: "Pyramid of biomass is upright in ____R____ and inverted in ____S____ ecosystem."
- **R**: The pyramid of biomass is upright in a **terrestrial ecosystem** (like grasslands) where the biomass of producers is greater than that of consumers.
- **S**: It is inverted in an **aquatic ecosystem**. In aquatic systems, large carnivores (like sharks) can have a higher biomass than the smaller producers (like phytoplankton).

3. **Statement (iii)**: "Gases like `CO_2` allow the ___T____ wave heat radiations of sun to reach the earth's surface but do not allow the ____U____ wave heat radiations reemitted by earth to escape, thereby causing ____V_____ flux."
- **T**: Gases like `CO_2` allow the **short** wave heat radiations of the sun to reach the earth's surface.
- **U**: They do not allow the **long** wave heat radiations reemitted by the earth to escape.
- **V**: This causes **greenhouse** flux, as it leads to the trapping of heat in the atmosphere.

4. **Statement (iv)**: "Large amount of ____W____ is added to the atmosphere by marshes, paddy fields and biogas plants."
- **W**: A large amount of **methane** is added to the atmosphere by these sources. Methane is a potent greenhouse gas released from anaerobic decomposition in marshes, paddy fields, and biogas plants.

### Final Answers:
- P: Grassland ecosystem
- Q: Parasitic food chain
- R: Terrestrial ecosystem
- S: Aquatic ecosystem
- T: Short
- U: Long
- V: Greenhouse
- W: Methane