Slip is the clay that has been watered down to the consistency of paint, used primarily by the Greeks to decorate and "glue" pieces together.
Slip is mostly used in pottery, which is a mixture of clay and other materials suspended in water, used to glue pieces together or to paint a piece, mixes coloring sometimes to the mixture, and is used as paint in pottery.
Thus, the correct option is A, Slip is clay that has been watered down to the consistency of paint.
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