A G1P0 with spontaneous abortion in previous pregnancy ,,now came with amenorrhoea

A G1P0 with spontaneous abortion in previous pregnancy ,now came with amenorrhoea …
.her FSH =6 IU/L…what is the cause for her amenorrhoea ???( AIIMS NOV 2018)…

1)Ovarian failure …
2)Fresh pregnancy …
3)pituitary failure …
4)Uterine synechia …

Ans 4