I have had the coffee.指现在完成时
It doesn't taste like anything I have ever had before.意思是说我从来没有品尝过这么好的咖啡
首先排除A,I have 就不能用 before了
C,I had ever had 就成了过去完成时,过去完成指过去的过去
语句中是现在的过去,所以用现在完成时have ever done sth.
故选B