Which is Earth's thinnest layer? (a) crust (b) inner core (c) mantle (d) outer core

Step 1: Define the Problem

Identify which of Earth's layers is the thinnest among the given options.

Step 2: Break Down the Problem

Examine each layer of the Earth: crust, inner core, mantle, and outer core, to determine their relative thickness.

Step 3: Apply Relevant Concepts

• Crust: The outermost layer of the Earth, relatively thin compared to other layers.
• Mantle: Located beneath the crust, much thicker than the crust.
• Outer Core: Below the mantle, thicker than the crust.
• Inner Core: The innermost layer, thicker than the crust but smaller in volume compared to the mantle and outer core.

Step 4: Analysis, Verify and Summarize

• The Earth's crust is the outermost layer and is significantly thinner than the other layers.
• The mantle, outer core, and inner core are all thicker than the crust.

Final Answer

(a) crust