The correct answer is A. Vibro pile.
Vibro piles are driven into the ground by a vibratory hammer. The vibration loosens the soil and allows the pile to be driven more easily. Vibro piles are often used in soft soils, such as clay or silt.
Pressure piles are driven into the ground by a hydraulic hammer. The hammer exerts a large amount of pressure on the pile, which drives it into the ground. Pressure piles are often used in hard soils, such as sand or gravel.
Franki piles are driven into the ground by a drop hammer. The hammer drops onto the pile, which drives it into the ground. Franki piles are often used in very hard soils, such as rock.
Pedestal piles are large, concrete blocks that are placed on the ground. The weight of the block helps to support the structure. Pedestal piles are often used in shallow foundations.
In places where the soil is soft and has small resistance to the flow of concrete, vibro piles are the best option. Vibro piles are driven into the ground by a vibratory hammer, which loosens the soil and allows the pile to be driven more easily. This makes them ideal for use in soft soils, where other types of piles may be difficult to drive.