Which of the following is CORRECTLY matched ?

Options

A. Frog - Primary consumer
B. Productivity - `"Kcal"//m^2//yr`
C. Tertiary consumers - Slime moulds
D. Temperate ecosystem - Ocean

Answer

To solve the question "Which of the following is CORRECTLY matched?", we will analyze each option provided in the context of food chains and ecological classifications.

### Step-by-Step Solution:

1. **Analyze the First Option: Frog as Primary Consumer**
- In a typical food chain, the primary consumers are herbivores that feed on primary producers (plants). Frogs are generally considered secondary consumers because they primarily eat insects (which are primary consumers).
- **Conclusion**: This option is incorrect.

2. **Analyze the Second Option: Productivity**
- Productivity refers to the rate of synthesis of biomass in an ecosystem. It is often measured in terms of energy, typically expressed in kilocalories per square meter per year.
- **Conclusion**: This option is correct.

3. **Analyze the Third Option: Tertiary Consumers and Slime Moulds**
- Tertiary consumers are typically carnivores that eat secondary consumers. Slime moulds are not classified as tertiary consumers; they are decomposers.
- **Conclusion**: This option is incorrect.

4. **Analyze the Fourth Option: Temperate Ecosystem and Ocean**
- Oceans are classified as marine ecosystems, not temperate ecosystems. Temperate ecosystems refer to specific terrestrial environments, typically found in temperate climate zones.
- **Conclusion**: This option is incorrect.

### Final Conclusion:
The only correctly matched option is the second one regarding productivity.