Ovarian Estrogen Question

[wrathofgod64]

So I'm a bit confused on this question that appeared in Kaplan FL #3

A normal female rat injected with estradiol will respond by:
A. decreasing secretion of LH from the anterior pituitary.
B. increasing secretion of LH from the anterior pituitary.
C. decreasing secretion of GnRH from the hypothalamus.
D. increasing secretion of progesterone from the follicle.

My answer was A, since an increase in estradiol will cause a negative feedback effect on LH and FSH. However, the answer was B, and the reason they gave estrogen has a positive feedback effect on LH and FSH. I feel that's only true prior to the LH surge, but otherwise estradiol should have a negative feedback effect on LH and FSH. Can someone explain this to me?

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[HawkeyePostOp]

Looks like they meant a sudden increase in estradiol, which causes a luteal surge by positive feedback. Roughly normal levels of estradiol, not specifically increases of estradiol, inhibit FSH and LH.

I suppose if they wanted the negative feedback answer they may have said "a normal female rat was gradually given low doses of estradiol." Not the best worded question.