What is the purpose of the Bender Element instrument in soil mechanics?

To measure the velocity of a shear wave in a soil sample.
To determine the maximum shear modulus (Gmax) for deformation levels up to 0.001%.
To analyze the degradation of the soil.
To determine the soil's resistance to cutting forces.
a) I and II are correct.
b) II and III are correct.
c) I and IV are correct.
d) II and IV are correct.