Greatest biological problems faced by human beings is :

Options

A. Population explosion
B. Depletion of ozone layer
C. Depletion of natural resources
D. Land erosion

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question:**
The question asks for the greatest biological problem faced by human beings. This requires us to analyze the options provided and determine which one has the most significant impact on human life and the environment.

2. **Analyzing the Options:**
- **Option A: Population Explosion**
- Definition: A rapid and dramatic increase in the world's population.
- Impact: This leads to overpopulation, which can strain resources, lead to environmental degradation, and create challenges in providing adequate food, water, and healthcare.

- **Option B: Depletion of Ozone Layer**
- Definition: The thinning of the ozone layer due to pollutants.
- Impact: Increased UV radiation reaching the Earth's surface can lead to health issues such as skin cancer and cataracts, as well as environmental impacts.

- **Option C: Depletion of Natural Resources**
- Definition: The consumption of natural resources at a rate faster than they can be replenished.
- Impact: This can lead to scarcity of essential resources like water, minerals, and fossil fuels, affecting sustainability.

- **Option D: Land Erosion**
- Definition: The displacement of the upper layer of soil due to various factors.
- Impact: While it affects agriculture and land use, it is not as overarching a problem as the others listed.

3. **Identifying the Greatest Problem:**
After analyzing the options, it becomes clear that:
- **Population Explosion** (Option A) is the greatest biological problem as it encompasses various issues related to resource depletion, environmental degradation, and social challenges. It has a more significant and direct impact on human survival and quality of life compared to the other options.

4. **Conclusion:**
Therefore, the correct answer to the question is **Option A: Population Explosion**.

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