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

Explanation

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 contains a variety of elements, but we need to focus on the most abundant ones.

2. **List the Most Abundant Elements**:
According to geological studies, the most abundant elements in the Earth's crust are:
- Oxygen (O) - approximately 46%
- Silicon (Si) - approximately 28%
- Aluminum (Al) - approximately 8.3%
- Iron (Fe) - approximately 5.6%
- Other elements like Calcium (Ca), Sodium (Na), and Magnesium (Mg) are present in smaller amounts.

3. **Analyze the Options Given**:
Since the question implies that there are options provided (though not listed), we need to determine which elements are included in those options.

4. **Determine the Most Abundant from the Options**:
If the options include Aluminum and Iron, we can conclude that they are among the most abundant elements in the Earth's crust after Oxygen and Silicon.

5. **Select the Correct Answer**:
Based on the analysis, if the options provided are Aluminum and Iron, then this is the correct answer as they are the most abundant elements available in the Earth's crust after Oxygen and Silicon.

### Final Answer:
The most abundant elements in the Earth's crust, based on the options provided, are Aluminum and Iron.

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