下列各式中，与（x-1）2相等的是（ ）
A．x2-1
B．x2-2x+1
C．x2-2x-1
D．x2+1
（x-1）2=x2-2x+1．
故选B．
When the news came ______ the war broke out, he decided to serve in the army.[ ]
A. since
B. which
C. that
D. because
