Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.
Only with careful environmental planning can we protect the world in which we live.
A. Careful environmental planning protects the world we live in
B. Planning the environment carefully, we can protect the world in which we live.
C. Protecting the world we live in, we plan the environment carefully.
D. We can protect the world we live in only with careful environmental planning.