article: He was just an ordinary postman. Day after day, he shuttled  back and forth across the village. For him, life was without waves.
  One day, he was delivering mail as usual.When he looked up in the sky,he suddenly lost his balance.It was a little stone that tripped him up .He observed the stone that had embarrassed  him,finding it strange but beautiful.In his eyes,this stone was like a lost jewel covered with dust. The postman then placed the stone in his bag carefully. Because of this stone's arrival,his day was lightened. He suddenly had a bold thought--I can build a castle with such beautiful stones.How magnificent it will be!
  His ordinary life started to be different since then. He still delivered mail,but he collected every stone he could find along the way.All those dusty stones,in his eyes,glittered like diamonds.
  Gradually,his small bag couldn't hold his stones anymore and he needed to use a wheelbarrow to carry them.People didn't understand what happened when they saw the postman delivering letters with a wheelbarrow full of stones.
  After collecting enough stones,he started to build his castle.During the daytime,he passed along the dreams of others;and during the nighttime,he built his own dream.No one was willing to join in.But the postman was unmoved,still happily building his castle.Because he knew,the dream and the castle only belonged to him.
  After 20 years of working day and night,the postman's dream castle was finally completed.It was a magnificent castle just as he had imagined.It was a miracle arising from the ordinary.
  This is a real story.The postman's name is Xue Waller.The stone castle has become a famous tourist attraction in France,which is called"ideal palace of Ferdinand Cheval."At the entrance of the stone castle,there is a sentence--"I want to know how far a dream stone can go."
question: The postman named Xue Waller was   _  .
options: German French British American