If the maximum payload $($in tons$)$ of a TL shipment was determined to be less than the maximum weight capacity of

the truck trailer used for transportation, which one option below best illustrates the cause?

a$)$ The unit weight of the product is too high, which limits the number of units that can fit in the truck.

b$)$ The product's density is too low and will "cube out" the truck trailer before reaching its weight limit$.$

c$)$ The product's density is too high and will "weigh out" the truck trailer before reaching its weight limit$.$