It has been observed that soil pH increases in

Answer: Option C

Soil pH is a measure of the acidity or basicity of soil. Soil pH is a key characteristic that can be used to make informative analysis both qualitative and quantitatively regarding soil characteristics.
Soil pH is considered a master variable in the soils at affects many chemical processes. The optimum pH range for most plants is between 5.5 and 7.5.
It has been observed that soil pH increases in Winter.