42.aAccording to the passage, which of the following is correct?
(A) Most modern homes use two-wire electrical service.
(B) Three-wire electrical service has one hot wire.
(C) Lowering electric voltage is necessary for electricity use in a house.
(D) Local utility company provides direct current electricity.

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統計: A(1), B(1), C(4), D(2), E(0) #802370