Starting from the innermost layer and moving outward, arrange Earth’s spheres in a meaningful order: 1. Hydrosphere, 2. Atmosphere, 3. Biosphere, 4. Lithosphere.

Introduction / Context:
Earth-system questions test conceptual geography. The Earth has nested or interfacing “spheres” defined by materials and processes. If we imagine a vertical cross-section from inside toward outside, we can line up the layers in a coherent inner-to-outer order.

Given Data / Assumptions:

• Items: Lithosphere (4), Hydrosphere (1), Biosphere (3), Atmosphere (2).
• We interpret “inner to outer” relative to the solid surface upward.

Concept / Approach:
The lithosphere comprises the rigid crust and uppermost mantle and is the solid foundation beneath land and seafloor. Above it lies the hydrosphere (water bodies) over the solid crust. The biosphere, representing life, is superimposed across land/water and lower air layers. The atmosphere envelops all, extending far above the surface. For an inner-to-outer teaching sequence, a standard ordering is lithosphere → hydrosphere → biosphere → atmosphere.

Step-by-Step Solution:
Start with the solid base: Lithosphere (4).Above the solid crust is water: Hydrosphere (1).Life exists across and atop these: Biosphere (3).Outermost enveloping layer is air: Atmosphere (2).Thus: 4, 1, 3, 2.

Verification / Alternative check:
Some texts emphasize that the biosphere intersects other spheres. Even with overlap, a pedagogical inside-to-outside walk still arrives at 4 → 1 → 3 → 2 as the clearest “layering” narrative.

Why Other Options Are Wrong:

• Placing atmosphere before lithosphere ignores inner-to-outer direction.
• Putting biosphere first misrepresents life sitting atop physical layers.
• Hydrosphere cannot be outermost compared to atmosphere.

Common Pitfalls:
Forgetting that biosphere is not a strictly separate shell but a zone; students sometimes put it last or first without considering the physical base and the aerial envelope.

Final Answer:
4, 1, 3, 2