Rewrite the following sentences, using the words in brackets
Unless he changes his way of living, he'll meet a lot of troubles. (if)
A.If he doesn't changes his way of living, he'll meet a lot of trouble.
B.If he changes his way of living, he'll meet a lot of trouble.
C.If he doesn't changes his way of living, he would meet a lot of trouble.
D.If he changes his way of living, he'll not meet a lot of trouble.