Intermodal transportation in North America has increased in large part due to:

a$.$

improved service levels from railways after railway consolidation, deterioration of roads, bridges, and highways and the effect on trucking.

b$.$

increased reliability from technological and operational improvements.

c$.$

deterioration of roads, bridges, and highways and the effect on trucking.

d$.$

improved service levels from railways after railway cons

olidation.