Which of the following can be the best title for this article

A．the sky always turns gray only on weekends.
B．in the Midwest, weekdays saw larger daily temperature variations sometimes.
C．this difference measurement is called DTR, meaning the daytime temperature range.
D．part of the study involved 660 weather stations only in the United Nation.

A．Placing a piece of tissue paper between each layer of clothing will help prevent wrinkling.
B．You must stuff your shoes with underwear or socks and other valuables so they won't be crushed during your travels.
C．Pack each item one at a time in a clockwise direction.
D．Check with the Transportation Security Administration to verify that the items you are carrying on the plane are allowed onto the aircraft.