Choose one sentence that has the same meaning to the root one:
Dinosaurs became extinct millions of years ago because the earth ‘s climate changed drastically.
If the earth’s climate had changed drastically, dinosaurs would have become extinct.
If the earth’s climate had not changed drastically, dinosaurs would have become extinct.
If the earth’s climate had not changed drastically, dinosaurs would not have become extinct.
If the earth’s climate changed drastically, dinosaurs would not have become extinct.
If the earth’s climate had not changed drastically, dinosaurs would not have become extinct.