问题

While Helen _____ along the river after supper, she ____ a wallet lying on the roadside.
A:was walking; was finding
B:walked; foundB. walked; was finding D. was walking; found;
C:taken
D:was walking; found;
B:walked; foundB. walked; was finding D. was walking; found;
C:taken
D:was walking; found;
正确答案是: