challenge: Where is the Sanguantang Bridge located?
  
  A. Luoxing Subdistrict, Jiangsu, China
  B. Jiashan County, Anhui, China
  C. Luoxing Subdistrict, Fujian, China
  D. Luoxing Subdistrict, Jiashan County, Zhejiang, China
  Answer: 