A bird flew into Annie's house while opening the window.

Choose the answer that is the most effective substitute for the underlined part of the sentence. If no substitute is necessary,

choose 'Leave as is.'

A)Leave as is.


B)Opening the window, a bird flew into Annie's house.


C)While opening the window, a bird flew into Annie's house.


D)While Annie was opening the window, a bird flew into her house.