You are planning to connect your three branch offices to the corporate site via Frame Relay. The first branch office has been assigned the network 10.1.0.0/16， the second 10.2.0.0/16， the third 10.3.0.0/16， and the corporate headquarters uses 10.0.0.0/16. You would like to summarize all branch and corporate networks into a single route at the corporate site. Which network address and subnet mask should you choose？（）

A. 10.0.0.0/24
B. 10.0.0.0/16
C. 10.0.0.0/14
D. 10.0.0.0/15