Which paragraph explains what made Smith’s model e...

D

- Hướng dẫn giải

Phương pháp giải:

Giải chi tiết:

Đáp án là D. Ngay câu đầu tiên trong đoạn 2: Smith achieved efficiency in his model by designing a system that was separate from the passenger system and could, therefore, focus on how to deliver packages most efficiently