The most abundant element in earth's crust is

Options

A. Aluminium
B. Silicon
C. Carbon
D. Oxygen

Answer

To determine the most abundant element in the Earth's crust, we can follow these steps:

### Step 1: Identify the Elements
We need to consider the common elements found in the Earth's crust. The options given are:
1. Aluminium
2. Silicon
3. Carbon
4. Oxygen

### Step 2: Research the Abundance of Each Element
Next, we will look at the approximate abundance of each element in the Earth's crust:
- **Oxygen**: Approximately 46.1%
- **Silicon**: Approximately 28.2%
- **Aluminium**: Approximately 8.23%
- **Iron**: Approximately 5.63%
- **Carbon**: Much less than the above elements.

### Step 3: Compare the Percentages
Now, we compare the percentages of these elements:
- Oxygen (46.1%)
- Silicon (28.2%)
- Aluminium (8.23%)
- Iron (5.63%)
- Carbon (significantly lower)

### Step 4: Determine the Most Abundant Element
From the comparison, it is clear that Oxygen has the highest percentage in the Earth's crust.

### Conclusion
Thus, the most abundant element in the Earth's crust is **Oxygen**.

### Final Answer
The correct option is **4. Oxygen**.

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