What percentage of plants' absorbed water typically does not contribute to photosynthesis?

The correct choice indicating that around 10% of the water absorbed by plants typically does not contribute to photosynthesis is based on the understanding of plant physiology. In plants, water plays several essential roles beyond photosynthesis, such as maintaining cellular turgor pressure, transporting nutrients and minerals from the soil, and participating in metabolic processes.

During photosynthesis, plants utilize water molecules to produce glucose and oxygen. However, only a portion of the total water taken up by roots is directly used in this process. The majority of the water absorbed is utilized for other functions such as transpiration, where water evaporates from the surface of leaves, aiding in temperature regulation and nutrient uptake.

This means that the proportion of absorbed water contributing directly to photosynthesis is greater than that which does not, thus validating the selection of approximately 10% as the water that is not used in the photosynthetic process.