.......... at by everyone, he was disappointed.

A

- Hướng dẫn giải

Phương pháp giải:

Giải chi tiết:

A

Giản lược mệnh đề khi cùng chủ ngữ

Laughed at by everyone, he was disappointed. = (Because) he was laughed at by everyone, he was disappointed. = Bị mọi người cười, anh ấy đã rất thất vọng.