Recent Pressures for Protectionism in the United States Have Been $\underline {\text { except }}$

Recent pressures for protectionism in the United States have been motivated by all of the following $\underline {\text { except }}$ :

A) U.S. firms shipping component production overseas
B) High profit levels for American corporations
C) Sluggish rates of productivity growth in the United States
D) High unemployment rates among American workers