The correct option is D stalemate
Stalemate means a situation in which neither group involved in an argument can win or get an advantage and no action can be taken. No government can make any further nuclear tests till a decision is reached. Hence, Option D is correct. Among the rest of the options, moratorium means a temporary prohibition of an activity, controversy means prolonged public disagreement or heated discussion, insight means an accurate and deep understanding, rapproachment means an establishment or resumption of harmonious relations.These options do not express the intended meaning, hence incorrect.