单选题：For code below, the result would be?

For code below, the result would be? @[A](2)
```Java
String s = "Welcome to Zhejiang University";
String[] a = s.split(" ");
System.out.println(a.length);
```
A. 4
B. 3
C. Compile error
D. Run-time exception




A.4
B.3
C.Compile error
D.Run-time exception


答案：A