Concept:The sentence tests the correct idiomatic phrase meaning to stop completely.
Explanation:The power cut caused production to stop completely.
The correct phrase is “came to a stand still”.
This phrase means to remain fixed or motionless.
A “hold-up” means a delay, not necessarily a full stop.
A “blockade” is an obstacle, which does not fit here.
“Suspense” means anxious waiting, which is unrelated to production.
Therefore, the best word to complete the sentence is option C.
Answer:C. stand still