An uncontrolled railroad crossing usually has a crossbuck and a round, yellow sign. traffic-signal lights. a crossing gate and red lights. a YIELD sign, and sometimes a STOP sign.

## Step 1<br />This problem is about identifying the typical features of an uncontrolled railroad crossing. An uncontrolled railroad crossing is a type of crossing where there are no traffic control devices such as signals or gates to regulate the flow of traffic.<br /><br />## Step 2<br />The options provided are:<br />- a crossbuck and a round, yellow sign.<br />- traffic-signal lights.<br />- a crossing gate and red lights.<br />- a YIELD sign, and sometimes a STOP sign.<br /><br />## Step 3<br />Among these options, the first one, which includes a crossbuck and a round, yellow sign, is the most common feature of an uncontrolled railroad crossing. A crossbuck is a sign that indicates a level crossing, and the round, yellow sign is a warning sign that alerts drivers to the presence of a railroad crossing ahead.