In the children's playground, photographers shoot cartoon characters. When focusing, he found the position of cartoon characters on ground glass as shown in Figure 5-2A.

Analysis: when the convex lens becomes a real image, compared with the object, the image should be interchanged up and down. According to the position of the image in Figure A, determine the position of the main optical axis of the convex lens where the object is located, and then adjust it. Solution: Solution: Figure A is the upper left image of frosted glass, indicating that cartoon characters are below the right side of the main optical axis of the convex lens. To make the image as shown in Figure B, it is necessary to adjust the cartoon characters to the main optical axis of the convex lens, so the lens should be moved to the lower right.

So choose B. Comments: The key point of this question is to find out the direction of the object in the lens and adjust the object to the main optical axis. If the cartoon character moves, it should move to the upper left corner. So choose C, I hope it helps you.