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