Question

Sitting patiently, my mother read a magazine in the waiting room. A. Sitting patiently B. in the waiting room C. my mother read D. read a magazine

Answer 1

The participial phrase here is A, sitting patiently. Because all other answers are not correct. In the waiting room is adverbial phrase for place, my mother read is just a regular sentence, not a phrase, as well as read a magazine. So the answer is A, sitting patiently, as sitting is present participle.