Question

The element whose percentage weight is highest in both earth's crust and human body is

• A. Hydrogen
• B. Carbon
• C. Oxygen
• D. Calcium

Answer 1

The Correct Option is C

In both the Earth's crust and the human body, the element with the highest percentage by weight is oxygen.

The Earth's crust is the outermost layer of the Earth, lying above the mantle. It is a solid, rigid layer that is relatively thin compared to the Earth's other layers, such as the mantle and core. The Earth's crust is made up of a variety of rocks and minerals and plays a crucial role in the structure and functioning of the planet.

The Earth's crust is mainly composed of silicon and oxygen, with common minerals such as feldspar, quartz, mica, and basalt (in oceanic crust) and granite (in continental crust).

• Hydrogen (A): Abundant in the human body (e.g., in water) but not the highest by weight. Minimal in Earth's crust.
• Carbon (B): Essential for organic molecules but ranks lower in weight percentage.
• Oxygen (C): Correct answer—constitutes ~46% of Earth's crust (by weight) and ~65% of the human body (primarily in water and biomolecules).
• Calcium (D): Significant in bones but far less abundant than oxygen.

Thus, the answer is (C) Oxygen.

Answer 2

Oxygen dominates the composition of both the Earth’s crust and the human body by weight. In the Earth’s crust, oxygen accounts for approximately 46.6%, primarily bound in silicates, oxides, and water. In the human body, oxygen makes up about 65% of the weight, as it is a key component of water, proteins, carbohydrates, and lipids. While other elements like carbon and hydrogen are vital for life, their percentage by weight is significantly lower. This dual prevalence underscores oxygen’s fundamental role in geology and biology.

Thus, the answer is (C) Oxygen.