问题补充：
Our city is becoming .
A. more and most beautiful
B. more beautiful and more beautiful
C. more and more beautiful
D. beautiful and beautiful
答案：
A. more and most beautiful
B. more beautiful and more beautiful
(答案→)C. more and more beautiful
D. beautiful and beautiful
解析：结合语境可知本句指的是，我们的城市变得越来越美丽了，固定句式more and more……越来越……，故选C。
