Answer :
Final answer:
The subject of this question is Social Studies, and it is about railroad advance warning signs (circular and crossbuck signs). The correct options for the given signs are A) Circular and C) Crossbuck.
Explanation:
The subject of this question is Social Studies. Specifically, it is related to the topic of railroad advance warning signs. These signs include circular and crossbuck signs, which are used to indicate the presence of a railroad crossing ahead. The correct options for the given signs are A) Circular and C) Crossbuck. The circular sign warns drivers of a railroad crossing ahead, while the crossbuck sign is a white, X-shaped sign with the words 'RAILROAD CROSSING' on it.
