![](https://lstatic.shangxueba.com/jiandati/h5/images/m_q_title.png)
There is a U. N. convention that can cover ______.A.problem between neighborsB.problems on
There is a U. N. convention that can cover ______.
A.problem between neighbors
B.problems on air pollution
C.problem between states which do not share a border
D.trans-boundary air pollution