The long term prospects for a truly human civilisation depend in a large measure on

Options

A. the ability of humanity to moderate its fecundity
B. increasing the food production
C. colonisation of under polulated area
D. control of human diseases

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the long-term prospects for a truly human civilization and what factors are crucial for its sustainability and growth.

2. **Analyzing the Options**: The options provided are:
- A) The ability of humanity to moderate its fecundity (fertility).
- B) Increasing food production.
- C) Colonization of underpopulated areas.
- D) Control of human diseases.

3. **Evaluating Each Option**:
- **Option A**: Moderating fecundity can help control population growth, but if done excessively, it might lead to a decrease in population.
- **Option B**: Increasing food production is vital to prevent starvation and ensure health, but it is not the immediate solution if diseases are rampant.
- **Option C**: Colonizing underpopulated areas can help distribute the population better, but it does not address the immediate threats to human life.
- **Option D**: Controlling human diseases is crucial as it directly impacts mortality rates. If diseases are managed effectively, the population can grow and sustain itself.

4. **Determining the Most Crucial Factor**: Among the four options, controlling human diseases is the most important factor. By reducing mortality rates caused by diseases, the population can thrive, which in turn allows for better food production and population management.

5. **Conclusion**: Therefore, the long-term prospects for a truly human civilization depend primarily on the control of human diseases.

### Final Answer:
The long-term prospects for a truly human civilization depend in a large measure on the control of human diseases.

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