The X in the hazardous materials column of a shipping paper entry has which of the following meaning:

A The entry is for a hazardous material.

explanation

Learn to recognize shipments of hazardous materials. To find out if the shipment includes hazardous materials, look at the shipping paper. Does it have:
An entry with a proper shipping name, hazard class, and identification number?
A highlighted entry, or one with an X or RQ in the hazardous materials column? [Commercial Driver’s License Manual]