16.this is a purely _______ problem, not a political one.
a. additional b. assiduous
c. adamant d. academic
academic adj.学术的、理论的
additional 额外的、附加的
additive 添加剂
addendum 补充、附录
adder 蝰蛇
deaf as an adder 充耳不闻
assiduous 勤奋的、好学的
insidious 阴险的、狡诈的
preside (over) 主持
consider 考虑
adamant 固执的