Select the correct sentence.
A.
She​ hasn't danced for a long time because she will have broken her leg last month.
B.
She​ hasn't danced for a long time because she broke her leg last month.
C.
She​ hasn't danced for a long time because she was breaking her leg last month.
D.
She​ hasn't danced for a long time because she breaked her leg last month.