1. The problem statement, all variables and given/known data 2. Relevant equations I'm not sure any, perhaps 1/v + 1/u = 1/f 3. The attempt at a solution I knowp enlargened real images will only be produced if the object distance is lower than the image distance, so that rules out B. Similarly I know that enlargened virtual images can only be produced if the object distance is less than the image distance, so that rules out D. I'm not sure how to figure whether it's A or C, playing around in applets I can produce an image twice as big under both conditions.