Soil pH in Haryana is mostly:

Neutral to slightly alkaline
Highly alkaline
Highly acidic
Varies greatly across regions

The correct answer is: Varies greatly across regions.

Soil pH is a measure of how acidic or alkaline a soil is. It is measured on a scale of 0 to 14, with 7 being neutral. Soils with a pH below 7 are acidic, while soils with a pH above 7 are alkaline.

The pH of soil can vary greatly depending on the type of soil, the climate, and the presence of certain minerals. In Haryana, the pH of soil can vary from slightly acidic to highly alkaline. This is due to the fact that Haryana has a variety of different soil types, including alluvial, sandy, and loamy soils. The climate in Haryana is also quite diverse, with hot, dry summers and cool, wet winters. This variation in climate can also affect the pH of soil.

The presence of certain minerals can also affect the pH of soil. For example, limestone is a mineral that can make soil alkaline. In Haryana, there are some areas where limestone is present, which can explain why the pH of soil in these areas is higher than in other areas.

Overall, the pH of soil in Haryana varies greatly across regions. This is due to the fact that Haryana has a variety of different soil types, a diverse climate, and the presence of certain minerals.