Question

which interaction involves only one of earths spheres?
plant roots take in water from the soil.
plants take in carbon dioxide from the air.
during photosynthesis, plants make food and release oxygen into the air.
energy stored in plants is transferred to humans and animals that eat them.

Explanation:

Plant roots taking in water from the soil involves only the geosphere (soil) and the biosphere (plants). The other options involve multiple spheres such as the atmosphere - plants taking in carbon - dioxide from the air and releasing oxygen during photosynthesis, and energy transfer from plants to humans/animals which involves the biosphere and potentially the hydrosphere and atmosphere in the food - chain and energy - cycle context.

Answer:

Plant roots take in water from the soil.