以下选项中循环结构合法的是 （ ）
A:int j=3;while(j) { System.out.println(“ j is “ j); }
B:int j=0; do{System.out.println( “j is “ j );if (j = = 3) {continue loop;} }while (j<10);
C:while (int i<7){ i ;System.out.println(“i is “ i); }
D:int j=0; for(int k=0; j k !=10; j ,k ){ System.out.println(“ j is “ j “k is” k); }