The correct answer is: A. An aqueduct.
An aqueduct is a structure that carries water across a valley, road, or other obstacle. It is typically a long, elevated bridge with a series of arches that support the water channel. Aqueducts are often used to transport water from a source, such as a river or lake, to a destination, such as a city or irrigation system.
In the case of the proposed canal, the drainage bed level at C3 is the lowest of the three. This means that the canal will need to be built at a higher elevation at C3 in order to cross the drainage. An aqueduct is the best option for this purpose because it can be built to support the weight of the canal and the water it will carry.
A syphon aqueduct is a type of aqueduct that uses the principle of siphoning to transport water. A syphon is a curved tube that allows water to flow from a higher elevation to a lower elevation without the use of pumps. Syphon aqueducts are often used to transport water over long distances or to cross valleys or other obstacles.
A super passage is a type of bridge that is used to carry a road or railway over a valley or other obstacle. Super passages are typically much larger than aqueducts and are often used in mountainous areas.
A syphon is a type of pipe that is used to transport water or other liquids from a higher elevation to a lower elevation. Syphons work by using the principle of atmospheric pressure to create a vacuum that draws the liquid through the pipe. Syphons are often used in irrigation systems and to drain flooded areas.
In conclusion, the correct answer is: A. An aqueduct.