Tom is working with a layer on a graphic design project, and he wants to add a mask for the entire layer. What should he first ensure? A. that no part of the image is changed, by using a Lock switch
B. that some part of the image is revealed, by choosing Select
C. that no part of the image is selected, by choosing Deselect
D. that some part of the image is darkened, by using the Burn tool
E. that some part of the image is made lighter, by using the Dodge tool​