The angle of repose of a soil is the maximum angle which the outer face of the soil mass makes A. With the horizontal B. With the vertical C. With the perpendicular to the inclined plane of the soil D. None of these

The correct answer is A. With the horizontal.

The angle of repose is the maximum angle at which a soil mass can stand without sliding. It is measured between the horizontal and the outer face of the soil mass. The angle of repose is affected by the type of soil, the moisture content of the soil, and the slope of the surface.

Option B is incorrect because the angle of repose is not measured with the vertical. The vertical is a line that is perpendicular to the ground. The angle of repose is measured with the horizontal, which is a line that is parallel to the ground.

Option C is incorrect because the angle of repose is not measured with the perpendicular to the inclined plane of the soil. The perpendicular to the inclined plane of the soil is a line that is perpendicular to the inclined plane. The angle of repose is measured with the horizontal, which is a line that is parallel to the ground.

Option D is incorrect because the angle of repose is a real thing. It is the maximum angle at which a soil mass can stand without sliding.