Question

select the correct answer.
which of these processes was able to occur in earth’s early lithosphere before living organisms existed?
a. corrosion of metals
b. oxidation of minerals
c. erosion of soil
d. combustion of fuels

Explanation:

• Option A: Corrosion of metals requires the presence of metals and an oxidizing environment (often with water and oxygen). Early Earth's lithosphere had little to no refined metals (metals were in mineral forms), so corrosion of metals (like we see with refined metals now) didn't occur before organisms.
• Option B: Oxidation of minerals can occur through natural geological processes (e.g., reaction with atmospheric gases like CO₂, or water) without living organisms. Minerals in the early lithosphere could react with available oxidizing agents (like oxygen from volcanic outgassing or other non - biological sources) to undergo oxidation.
• Option C: Soil erosion requires the presence of soil. Soil formation is a process that involves the action of living organisms (like decomposition, plant root activity) over time. Before organisms existed, soil as we know it (with organic matter and structured by biological activity) didn't exist, so soil erosion couldn't occur.
• Option D: Combustion of fuels (like fossil fuels or biomass) requires fuel sources and an oxidizer. Fossil fuels are formed from organic matter (which requires organisms), and biomass is from living organisms. So before organisms, there were no fuel sources for combustion.

Answer:

B. oxidation of minerals