The current administration, being worried over some foreign trade barriers being removed and our exports failing to increase as a result of deep cuts in the value of the dollar, has formed a group to study ways to sharpen our competitiveness.

(C) worried about the removal of some foreign trade barriers and the failure of our exports

这个答案，但我不明白，has formed不是主语谓语吗，虽然c的表达最好，但是怎么解释worried的作用呢？