DIOXINS ARE DANGEROUS CHEMICALS… THEY CAN CAUSE CANCER AND BIRTH DEFECTS

15. - BAI TAP TIENG ANH LOP 9 TRAC NGHIEM TU BAI 1 10
Lớp 9 BAI TAP TIENG ANH LOP 9 TRAC NGHIEM TU BAI 1 10

15. Dioxins are dangerous chemicals… they can cause cancer and birth defects.

a. but b. however c. because .