A 1.5-year-old spayed female cat presents with a 7-day history of vocalizing, rolling, and allowing a male neutered cat in the household to mount her. The cat has gone through one similar episode 1 month ago. She otherwise has been behaving normally and has no other health problems. You performed an ovariohysterectomy on the cat at 3 months of age.
一只1.5岁雌性已绝育猫，由于过去七天以来持续出现嚎叫、翻滚以及允许家里其它公猫爬跨等行为前来就诊。一个月以前这只猫就出现过类似的情况。除此之外，一切正常，看起来没什么其它的问题。三个月前，你刚为这只猫做过子宫卵巢摘除术。
You perform vaginal cytology which shows some cornified epithelial cells but is inconclusive. You measure serum lutenizing hormone of 0.2 ng/ml (normal for an ovariectomized female is >1 ng/ml). Which of the following is the most appropriate course of action？
你为它做了阴道抹片只看到看少量角化上皮细胞，并没有什么提示意义。你检测了它的血清促黄体素水平为0.2 ng/ml（正常情况下已绝育的雌性动物该激素水平>1 ng/ml）。下一步该做什么？
A - Measure serum testosterone levels 测量血清雄性激素水平
B - Measure serum estrogen and progesterone levels 测量雌激素和孕激素水平
C - Order MRI of the brain to rule out a pituitary tumor 做脑补MRI排除垂体瘤
D - Exploratory laparotomy to remove the ovarian remnant 剖腹探查摘除卵巢残迹