After coupling, you should crawl under the trailer to check:

That the locking jaws are around the shank of the kingpin.. Section 6.4: Visually verify the connection by looking at the jaws and kingpin

After coupling, you should crawl under the trailer to check:

ANSWER BREAKDOWN
  • A. Incorrect. "The tires." is not correct. Visually verify the connection by looking at the jaws and kingpin from underneath.
  • B. Correct. Visually verify the connection by looking at the jaws and kingpin from underneath.
  • C. Incorrect. "The oil." is not correct. Visually verify the connection by looking at the jaws and kingpin from underneath.
  • D. Incorrect. "The lights." is not correct. Visually verify the connection by looking at the jaws and kingpin from underneath.