Which north korean action in the 2000s resulted in condemnation by other east asian countries?

a.
their attempts to trade with the united states

b.
their development of nuclear weapons program

c.
their attempt to invade china

d.
their peace treaty with japan

I believe the answer is: B. their development of nuclear weapons program

Since north Korean was't involved in any international peace agreement,  other east Asian countries view it as a threat to their national security.

In order to retaliate, many countries led by the united states imposed sanctions to north Korean companies in order to restrict their economy and slowed down the development program.