The relative proportion of sand, silt and clay in a soil is known

Answer: Option A

The relative proportion of sand, silt and clay in the soil is known as Soil texture. Soil separates are specific ranges of particle sizes like the smallest particles are clay particles and the largest one is a sand particle.
Soil texture is a classification instrument used in the field to determine soil classes based on their physical texture. It determines crop suitability and predicts the response of the soil to environment and management conditions.