ONCE _____, THIS PRODUCT SHOULD BE KEPT IN A COOL DARK PLACE. A. O...

12. - DE THI THU THPT MOONVN CUA CO MAI PHUONG CO DAP AN BAN WORD DE 2
DE THI THU THPT MOONVN CUA CO MAI PHUONG CO DAP AN BAN WORD DE 2
12. Once _____, this product should be kept in a cool dark place. A. opening B. having opened C. being opened D. opened