Which is a significant factor allowing the pipelines to increase their capacity and move an increased amount of tonnage?
a. larger pipe diameters
b. seamless pipe
c. major advances in technology
d. government regulations which require that the lines move product more quickly

a. larger pipe diameters

Explanation:

This is the factor that allows pipelines to increase their capacity and move an increased amount of tonnage. When we increase the diameter of a pipe, this allows a larger volume of material (water, oil, etc.) to move through it. This means that we are able to move a larger volume (tonnage) of material in a shorter amount of time. This increases the efficiency of the pipelines in a very significant way.