ANS:C - confining pressure

The principal factors affecting the shearing strength of cohesionless soil are;

1) Shape of particles.
2) Gradation.
3) Denseness.
4) Confining pressure.
5) Deviator stress.
6) Intermediate principal stress.
7) Loading.
8) Vibration and repeated loading.
9) Type of minerals.
10) Capillary moisture.