Indication of Manchester operation in prolapse:
This means option b and c both are correct. But though this operation was initially advocated for young women desirous of child bearing, now the view has changed -
"Cervical amputation may adversely affect subsequent conception (infertility, cervical stenosis) and/or pregnancy outcome (repeated IInd  trimester abortion, preterm labor, cervical dystocia). For these reasons, this repair is not considered as an operation of the choice in India" (for child bearing function).  - Principles and Practice of Obs & Gynae for PG's Pankaj Desai 3rd/ed p 559
In congenital elongation of cervix management is amputation of cervix which is just a part of Fothergill's repair, it does not require all components of this operation therefore, should not be considered amongst the correct options.
Nulliparous
Women of < 35 years age
Patient who wants child bearing function
Congenital elongation of cervix