The correct answer is A) Western. At morning stars, the last stars that should be observed are those with an azimuth in the western quadrant. This is because the western quadrant is the area of the sky where the sun is rising, and the last visible stars will be those located in the western part of the sky as the sky becomes brighter. The other options are incorrect because the eastern, northern, and southern quadrants are not where the last visible stars would be observed at morning stars.