题目：Returning from school, ______ .be found letter in the letter－boxB． letter ws found iReturning from school, ______ .be found letter in the letter-box B． letter ws found in the letter-box C． letter ws in the letter-box D．the letter-box hd letter in it
A．be found a letter in the letter-box
B．a letter was found in the letter-box
C．a letter was in the letter-box
D．the letter-box had a letter in it
