The section presents a question related to chemistry, specifically asking about an element commonly referred to as "vàng giả" (fool's gold). The options provided for the answer include:

A. Đồng (Copper)  
B. Bạc (Silver)  
C. Thủy ngân (Mercury)  
D. Platinum  

Key topics include the identification of elements and their common names, while the entities involved are the elements listed as answer choices.