49. Which sentence is the best "topic sentence" for the following paragraph?
__________For example, when we see someone gets hurt, we will also feel the same pain. On the other hand, when we know someone has an emotional breakdown, we may also find a similar connection with him or her. It is proved that our feelings influence our behaviors. If we are in a bad mood or we have just watched a negative movie, we will show less empathy to those in need. Scientists have found that "empathic distress" reduces happy factors in our brain. Because of this, we spend less time on others and focus more on ourselves.(A) People have the ability to share the feelings with each other.(B) Our brains know how to tell the differences between a happy or sad mood.(C) Empathic distress is the key to know if someone is focused or not.(D) The connections of people affect the interpersonal relationship.