45. 研究領導理論導向與理論整合是新趨勢，何種理論經常被用來整合不同理論？ (A)權變理論 (B)期望理論 (C)魅力理論 (D)願景式理論

3. Which of the following is a potential impact of an effective price ceiling?(A) a shortage(B) use of non-price factors such as discrimination to allocate the price-controlled good to consumers(C) deterioration in the quality of the price-controlled good(D) All of the above are potential impacts of an effective price ceiling.