He locked the door, ______. 选项: a、thus made sure no one woul

He locked the door, ______. 选项: a、thus made sure no one would interrupt him b、thus making sure
He locked the door, ______.
选项:
a、thus made sure no one would interrupt him
b、thus making sure no one would interrupt him
c、though made sure no one would interrupt him
d、although to make sure no one would interrupt him