The Danger with Geographic Clustering Occurs When Such Distinctness Occurs

The danger with geographic clustering occurs when such distinctness occurs at the broader macro level,resulting in what?

A) The cost of visiting Canada by residents of the U.S. is now more expensive than before
B) The ability of governments to effectively control economic expansion or contraction
C) The increased cost of developing new products and services
D) The inability of governments to effectively control economic expansion or contraction
E) The need to import skilled and well-educated workers due to a shortage domestically