By his/hers movements and by the way they talk. If they are acting afraid they are probably lying. And if they are in an overexcited mood they are also probably lying
By looking at the rest of the sentence to try to see how the word is being used.
Answer:
The top one is "People overdose 9-10 times a night"
Explanation:
His wife is the only character we are aware of doing that.
