When you drag a new image to your page, it automatically appears fully exposed and uncropped. If you want to resize the image without cropping it, use the corner handles on the selected image frame.
Dragging on the corner handles will increase or decrease the size of the image without cutting off the edges.
Dragging on top/bottom and side handles will crop your image. In the case of clipart, this is particularly not desirable.
If you have accidentally cropped your image or have dropped an image into a frame that is a different shape, drag the top/bottom or side handles to maximize the frame size to expose the entire image. Use the corner handles to resize it proportionally.