美国将我国的野生大豆与当地的栽培大豆杂交,培育大豆的新品种,利用的是生物多样[ ]
A.生物种类的多样性
B.基因的多样性
C.生态系统的多样性
D.以上说法都正确
答案:B
—Come on, please give me some ideas about the project.
—Sorry. With so much work _____ my mind, I almost break down.[ ]
A. filling
B. filled
C. to fill
D. being filled
从政治学的角度讲如何理解权力这一概念?