A、they are afraid of violence B、they are forbidden to go there C、there is great economic crisis there D、citizens there are fleei

This is the Church of the Nativity, the site that Christians venerate as the birthplace of Jesus Christ. It’s located in Bethlehem, one of the largest cities in the Palestinian territories.
  A decade ago, Manger Square which is just across the street from the Church of the Nativity would have been filled with thousands of tourists at this time of the year. However, last year, less than 3,000 tourists visited at Christmas time, down from an average of 90,000 at this time of the year less than a decade ago.
  This year does not look much better. Pilgrims still come to Bethlehem, but there are fewer in number. Fears over possible violence and an Israeli security barrier have kept them away. At the same time, many residents of this historical city are leaving, especially members of Bethlehem’s once majority Christian population. More than 3,000 Christians, about 10% of Bethlehem’s population have left the city since the Palestine intifada began 6 years ago. Now, even though the intifada is dormant, Christians continue to flee the city, crippling its once vibrant economy. The city hall of officials is struggling to cope with the effects of fleeing population and economic crisis in the Palestinian territories. But this year, the Islamic militant group Hamas refused to recognize Israel.