To determine if someone talking is telling the truth, watch for body language. IF the person is fidgeting, keeps looking away, or stumbles upon their words, there is a high possibility they aren't telling the truth.
Ask yourself if what they are saying is possible or makes sense
Answer
He speaks about eh subject as he were an expert. That should be correct.
C. It has 5 iambs (an iamb is 2 syllables that are unstressed and then stressed).