A:
Yes, it is compatible, also to check for other lens compatibilty for your D90, same as mine, FYI, I went to www.nikon.com to the lens simulator (http://imaging.nikon.com/lineup/lens/simulator/)....you can actually pair your camera with all the lenses compatibile with your camera and simulate using the photos they have available to actually show you how the picture looks before you decide to purchase the lens. Cool tool!!