Concept:Root hairs are specialized epidermal cells of plant roots that greatly increase the absorptive surface area.
Explanation:Root hairs are thin, elongated outgrowths that grow between soil particles.
They create a large surface area that helps the root make maximum contact with soil water.
Soil water enters the root hair mainly through the process of osmosis.
Osmosis occurs because the cell sap in the root hair has a higher solute concentration than the surrounding soil water.
This difference in concentration creates a water potential gradient.
As a result, water moves from the soil into the root hair across the selectively permeable cell membrane.
Root hairs do not excrete water or mineral salts, purify the soil, or translocate manufactured food.
Translocation of food is carried out by the phloem tissue, not by root hairs.
Therefore, the primary function of root hairs is absorption of water from the soil.
Answer:The function of the root hair in plants is to absorb soil water by the process of osmosis.
Correct option: A.