A yellow diamond sign showing a truck descending a steep slope warns of:

Correct answer: B – A steep downgrade ahead
Black-on-yellow signs warn of actual or potentially dangerous conditions ahead. The truck-on-slope symbol identifies a steep downgrade. The driver manual advises truck drivers to slow and shift to a lower gear, while all drivers should adjust their driving to the grade and other conditions indicated by the warning sign.
Source: Alaska Driver Manual — “Warning Sign”


