题目内容：
6The construct cobegin Statement1; Statement2; coend means Statement1 and Statement2 are to be executed in parallel. The only two atomic actions in this construct are loading thevalue of a variable and storing into a variablE.For the program segment x:=0； y:=O； cobegin begin x:=l; y:=y+x; end; begin y:=2; x:=x+3; end coend Which of the following indicate(s) possible values for the variables when the segment finishes execution? Ⅰ.x=1,y=2 Ⅱ.x=1,y=3 Ⅲ.x=4,y=6
A．Ⅰ
B．Ⅰ and Ⅱ
C．Ⅰ and Ⅲ
D．Ⅱand Ⅲ
参考答案：