If Constant Returns to Scale Apply to the Entire Range

Multiple Choice

If constant returns to scale apply to the entire range of production,then the long-run total cost curve would most likely:

A) be a straight line from the origin.
B) to increase at a decreasing rate initially,and then increase at an increasing rate.
C) to increase at an increasing rate initially,and then increase at a decreasing rate.
D) be U-shaped.