题目

 Although GM food is a scientific project ________ many scientists have been devoting their time and energy, many people in the world are doubting whether it’s worth the efforts.  A. to which          B. for which            C. about which     D. on which 答案：A2．已知一次函数y=（m-2）x-3的图象与一次函数y=$\frac{5-m}{2}$x+m的图象平行，求m的值．