The correct answer is: All of the above.
Auger boring is a method of drilling holes in the ground using a rotating auger bit. The auger bit is a hollow tube with cutting teeth on the outside. As the auger bit is rotated, it cuts into the soil and removes it from the hole.
Auger boring is a relatively quick and easy method of drilling holes in the ground. However, it is not suitable for all types of soil. Very hard soil, cemented soil, and very soft soil can all make it difficult to drill a hole using an auger bit.
In very hard soil, the auger bit may not be able to penetrate the soil. In cemented soil, the auger bit may not be able to cut through the cement. In very soft soil, the auger bit may sink into the soil and become stuck.
If you are unsure whether auger boring is suitable for your soil type, it is best to consult with a professional.