First of all, from this function, the independent variable is X, so we can see that its function image is symmetric about Y, excluding 1, 2. According to the nature of exponential function, the image of this function will not intersect with the X axis, so the image of this function can only be 3. Also, from the nature of exponential function, 2a-3 "0, so we exclude A.B.C and choose D.