A yellow diamond sign showing a short road entering the main road from the right means:

Correct answer: B. – A side road enters ahead
A yellow diamond sign with a short branch entering the main road warns of a side road ahead. It alerts you to an approaching intersection and the possibility of entering traffic. As a warning sign, it does not require all traffic to turn or prohibit a right turn.
Source: Oklahoma Driver Manual — Ch. 4, “Warning Signs—Black on a Yellow Background”



