Question 27 and 28 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. The former Serbian police chief has been jailed for ______.
A．killing 700 ethnic Albanians by himself B．burning 700 ethnic Albanians C．arresting 700 ethnic Albanians D．his role in the murder of more than 700 ethnic Albanians