1. A person buys a new toothbrush every quarter. Only two colors are available: blue and pink. If the person uses a blue toothbrush in a given quarter, the probabilities of buying a blue or pink toothbrush in the next quarter are 0.3 and 0.7, respectively. If the person uses a pink toothbrush in a given quarter, the probabilities of buying a blue or pink toothbrush in the next quarter are 0.5 and 0.5, respectively. Suppose the person buys a blue toothbrush in quarter 1. Given that the person buys a pink toothbrush in quarter 4, the probability that the toothbrush colors in quarters 2 and 3 are the same lies in which of the following ranges?
(A) Between 0.35 and 0.39
(B) Between 0.40 and 0.44
(C) Between 0.45 and 0.49
(D) Between 0.50 and 0.54

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