—Have you been to the painting show?
—Yes,the art works by some country children attracted visitors’ attention.
A.to be sent
B.having been sent
C.sent
D.being sent
—Have you been to the painting show?
—Yes,the art works by some country children attracted visitors’ attention.
A.to be sent
B.having been sent
C.sent
D.being sent
C
sent 和其逻辑主语art works是被动关系，相当于定语从句which were sent，作后置定语，表被动。