GMAT Critical Reasoning (CR) | Re: For the last five years, the XYZ Courier Company has made

We are looking for variables between regular delivery trips and personal trip.

Loading, unloading time doesn't matter so anything that focus upon that, we can exclude that as a weakener.

c) Many of the packages carried by XYZ between Town A and Town B are large, high-security packages, for which the processes of loading, unloading, and delivery can take up to half the length of the trip itself. => ruled out.

IMO A & E is also not weakener. a) The route between Town A and Town B
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