(1.0 điểm).

A A(1; 4), B(1; 1), C(3; 2) hoặc A(1; 4), B(3; 2), C(1;1)

B A(1; 4), B(3; 2), C(1;1)

C A(1; 4), B(1; 1), C(3; 2)

D A(1; 4), B(1; 3), C(3; 1)