求助:谁能帮我解答一道F2的题

四月魔豆

是F2教材一开始给的样题中的第25题. 没有答案，不知道怎么做。请各位学长给予指点，谢谢啦！
题目如下：
The following budgeted information relates to a manufacturing company for next period:
                           Units                                                                                $
Production        14,000                    Fixed production costs                    63,000
Sales                 12,000                    Fixed selling costs                          12,000

The normal level of activity is 14,000 units per period.
Using absorption costing the profit for next period has been calculated as $36,000.
问题是：What would the profit for next period be using marginal costing?

A    $25,000
B    $27,000
C    $45,000
D    $47,000

答案是哪一个呢?最好能简要解释一下.万分感激!