A number of elements are available in earth's crust but most abundant elements are___________

Options

A. Al and Fe
B. Al and Cu
C. Fe and Cu
D. Cu and Ag

Answer

To answer the question regarding the most abundant elements in the Earth's crust, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Elements in the Earth's Crust**:
- The Earth's crust is composed of various elements, but some are more abundant than others.

2. **List the Most Abundant Elements**:
- The most abundant elements in the Earth's crust, in order of their abundance, are:
- Oxygen (O)
- Silicon (Si)
- Aluminum (Al)
- Iron (Fe)

3. **Determine the Percentages by Weight**:
- The approximate percentages by weight of these elements in the Earth's crust are:
- Oxygen: 47%
- Silicon: 28%
- Aluminum: 8%
- Iron: 5%

4. **Analyze the Given Options**:
- The options provided are:
1. Aluminum and Iron (Al and Fe)
2. Aluminum and Copper (Al and Cu)
3. Iron and Copper (Fe and Cu)
4. Copper and Silver (Cu and Ag)

5. **Select the Correct Option**:
- Since the most abundant elements listed are Aluminum (Al) and Iron (Fe), the correct answer from the options provided is:
- **Option 1: Aluminum and Iron (Al and Fe)**.

### Final Answer:
The most abundant elements in the Earth's crust are **Aluminum and Iron (Al and Fe)**.

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