Hello there!
The first option is a personal juice, then it may not be a real fact.
The second option is a personal experience; even tho it is a fact, it shows it's an incomplete statement
The last option it's a prediction, something that may happen in a future. Thus, so far, it is not a fact.
In consequence, the only one correct answer is C. Robots are only useful in car manufacturing. It is a proven fact and a affirmation.
Hope this helps,
