老师,这道题 She walked across immense room ________ every one loo

老师,这道题 She walked across immense room ________ every one lookingh at her.
A.with B.as
因为没有逗号,我认为后句是表示状语从句,所以我选的as ,可是答案是A.
老师,如果room后面有逗号,
She walked across immense room ,________ every one lookingh at her.
是不是那个空就应该填that ? looking后面多打了一个h