Which element is the most abundant in the Earth's crust?

• A. Si (Silicon)
• B. O (Oxygen)
• C. Al (Aluminum)
• D. Fe (Iron)

Answer: (B)

Verified step by step guidance

1. Understand that the Earth's crust is composed of various elements, with some being more abundant than others based on geological studies and chemical analysis.
2. Recall that oxygen (O) is a major component of many minerals and rocks in the Earth's crust, often combined with other elements like silicon to form silicates.
3. Recognize that silicon (Si) is also very abundant but typically comes second to oxygen in terms of abundance in the crust.
4. Note that aluminum (Al) and iron (Fe) are important elements in the crust but are less abundant compared to oxygen and silicon.
5. Conclude that oxygen is the most abundant element in the Earth's crust because it forms the majority of the crust's minerals, especially silicate minerals.