Casio YC-400 User Manual page 62

Using Image Files Stored on the Computer's Hard Disk in a Presentation (PC Image Mode)
I To select multiple images that are not in a series
While holding down the [Ctrl] key on your computer keyboard, individually click the thumbnails
of each of the images you want to select. To deselect an image, hold down [Ctrl] as you
click it again. Holding down [Ctrl] when you click the thumbnail of an image selects or
deselects it without affecting any other images that are selected.
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