Well ma'am, you can have a look at the ad once again where it is written that "They(successful candidates) will be posted anywhere across Pakistan (whereas) officers selected for Finance, Office and Law cadres are likely to be posted at Head Office Karachi". Now a prudent answer to the question about the candidate's choice would be that "I am willing to be posted anywhere in Pakistan" in case of male candidates but as far as female candidates are concerned, it's very difficult for them to join the office outside of their residential cities.