For example, the area of three shapes between parallel lines () A. The largest area B. The largest area of parallelogram C. The largest area of trapezoid D. Triangle

Area of triangle = 12×3×h= 1.5h,

Trapezoidal area = (upper bottom +3)×h÷2, because the upper bottom is less than 3, the area is less than 3h.

So the area of parallelogram is the largest.

Therefore, choose: B.