7.Social and cultural activities for senior citizens ______ over the past several years.( )
0 136402 136410 136416 136420 136426 136428 136432 136438 136440 136446 136452 136456 136458 136462 136468 136470 136476 136480 136482 136486 136488 136492 136494 136496 136497 136498 136500 136501 136502 136504 136506 136510 136512 136516 136518 136522 136528 136530 136536 136540 136542 136546 136552 136558 136560 136566 136570 136572 136578 136582 136588 136596 151629
A. | conducted | B. | were conducted | ||
C. | have conducted | D. | have been conducted |