17. In the second paragraph, why does the author mention the challenges faced by public facilities at tourist spots?
(A)To demand that local governments stop all tourism-related construction immediately
(B)To explain why residents prefer to move to areas with more narrow and tightly packed streets
(C)To illustrate how the original scale of these locations is overwhelmed by the number of visitors
(D)To suggest that developing modern facilities is more important than preserving historical streets