01 What damage may occur if a natural-bristle brush is repeatedly washed with very hot water?
Answer and explanation
Correct answer: A. The bristles may weaken and lose shape
Explanation: The governing concept is safe care of natural bristles. Repeated exposure to very hot water can weaken natural hairs and may also affect the adhesive that holds them in the ferrule. Therefore, option A is correct: the bristles can lose strength and their original shape. The other choices describe impossible or unrelated effects; hot water does not turn a brush into metal, lengthen its handle, or make paint permanent.