Ans. is b i.e. Colposcopy and biopsy investigation of choice in post-coital bleeding in a 60 years old lady (which suggests carcinoma cervix) is Colposcopy and Biopsy. The aim of Colposcopy is : - to confirm the diagnosis - to identify the extent of lesion - it allows conservative treatment in case of precancerous lesions. Pap smear is not the investigation of choice, as it is a screening procedure. If pap smear is negative in this case (In postmenopausal females, where there are less metaplastic changes at squamo columnar junction) we still have to confirm by Colposcopy. Cone biopsy is a destructive method and is advised only if diagnosis cannot be confirmed by colposcopy or SCJ is not visualised.