Select the WRONG statements regarding carbon cycle.

Options

A. Oceanic water can retain upto 50 time the `CO_2` levels in the air
B. The only major reservoir of carbon in the biosphere is the lake
C. Volcanic eruptions, hotsprings, burning of fossil fuel and weathering add carbon dioxide into the atmosphere .
D. The recycling of carbon is a self regulating feedback system.

Answer

To solve the question regarding the wrong statements about the carbon cycle, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding the Carbon Cycle**: The carbon cycle is a natural process where carbon is exchanged among the atmosphere, land, water, and living organisms. It includes processes like photosynthesis, respiration, decomposition, and combustion.

2. **Analyzing the Options**:
- **Option A**: "Oceanic water can retain up to 50 times the CO2 level in the air."
- **Analysis**: This statement is true. Oceans absorb a significant amount of carbon dioxide from the atmosphere, and they can hold much more CO2 than the air.

- **Option B**: "The only major reservoir of carbon is the lake."
- **Analysis**: This statement is false. While lakes do contain carbon, they are not the only major reservoir. The major reservoirs of carbon include the atmosphere, oceans, soil, and fossil fuels, not just lakes.

- **Option C**: "Volcanic eruptions lead to the release of carbon dioxide."
- **Analysis**: This statement is true. Volcanic eruptions release CO2 and other gases into the atmosphere, contributing to the carbon cycle.

- **Option D**: "The recycling of carbon is a self-regulatory feedback."
- **Analysis**: This statement is misleading. The carbon cycle is influenced by various factors, including human activities and natural processes, but it is not strictly a self-regulatory feedback system. It is primarily regulated by biological processes, especially photosynthesis by plants.

3. **Conclusion**: The wrong statement regarding the carbon cycle is **Option B**: "The only major reservoir of carbon is the lake." This is incorrect as there are multiple reservoirs of carbon.

### Final Answer:
The wrong statement regarding the carbon cycle is **Option B**.