下面哪个是正确的运行结果？ class Example5_1 { public static void main(String args[]) { String s1,s2; s1=new String("we are students"); System.out.println(s1.equals(s2)); System.out.println(s1==s2); s1="how are you"; s2="how are you"; System.out.println(s1.equals(s2)); System.out.println(s1==s2); } }
选项：

A:true false true true
B:true true false true
C:true true true true
D:false true false true