This is a rather strange story but it is quite true. In December 1996, a burglar broke into a golf club in a small town. When the police arrived to look into it, they found an unusual clue--- a piece of cheese with a bite-mark in it. The burglar had gone into the kitchen, and had eaten some food there. Then he had stolen some cigarettes and a little money.               The police man in charge of the case guessed that the burglar was a local man. He thought that professional thieves would not bother to break into a golf club.He made enquires in the town and asked three suspects to come to the police station. When he questioned them about the burglary, they all denied stealing in the club.The policeman then gave each man a piece of cheese and asked them to bite it. He took the pieces of the cheese to a dentist and asked him to compare the bite-marks with that in the piece of cheese at the scene of the burglary.               The policeman set free two of the suspects and questioned the third one. At first the man said that he was innocent . The policeman knew that the man was lying, so he encouraged him to talk until he began to contradict himself  . The policeman told him about the bite-marks and the man had to admit his stealing. Which of the following words can be best used to describe the policeman?
Kind-hearted Intelligent Hard-working Encouraging