The correct answer is: D. Any point.
Setting out the alignments of sewers may start from any point. The most important thing is to ensure that the sewer is aligned in the correct direction and that it has the correct slope. The slope of the sewer is important to ensure that the sewage flows smoothly and does not back up.
The city, outfall, and tail end are all possible starting points for setting out the alignments of sewers. However, the starting point should be chosen based on the specific circumstances of the project. For example, if the sewer is being installed in a city, it may be necessary to start from the city center. If the sewer is being installed in a rural area, it may be possible to start from the outfall.
The most important thing is to ensure that the sewer is aligned in the correct direction and that it has the correct slope. The slope of the sewer is important to ensure that the sewage flows smoothly and does not back up.