I have come across this question often enough especially with people who are new to DSL cameras. Why can’t they select the focusing point with their camera. The camera seems to auto pick the subject which at times might not be right.
This is due to the default setting of your camera. To correct this, you need to find the Auto focus setting of your camera and set it to Single Point or other setting instead of Auto Area.
For Nikon D90, go to Menu > Custom Setting Menu (pencil icon) > AF-Area mode (a1) > Single Point
Tags: Autofocus mode, Nikon D90