Read the procedural text. Preparing a Wet-Mount Slide

Purpose: to view aquatic specimens under a microscope by suspending them in fluid
Materials: concave slide, cover slip, water, tweezers, pipette, paper towels, specimen
Steps in the procedure:
Use pipette to place a drop of water in the concave center of the slide.
Use tweezers to position the specimen in liquid.
Place one side of the cover slip on slide at the edge of the concave center.
Lower the cover slip slowly over the center and remove any water with the towel.
Which text feature, if used, would best help the reader understand the importance of lowering the cover slip slowly?

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