高二英语单选 ,

高二英语单选 ,
When I opened the door,I found my father sitting in his chair,completely ________ a
magazine.
A．absorbing in B．absorbed in C．absorbing to D．absorbed to
解析：此处absorbed in作伴随状语,意为“专心于”.
A为什么不行?found sb doing sth ,正在做某事呀?、、