66 Travelers are urged to use _________ repellent and wear long-sleeved shirts and long pants when outdoors to prevent mosquito bites.
(A)insect
(B)portion
(C)appeal
(D)leisure

建議旅客在戶外活動時使用驅蚊劑，並穿著長袖襯衫和長褲，以防止蚊蟲叮咬。