Most common type of human papilloma virus causing Ca cervix are:
It is now established that HPV plays a major role in cervical carcinogenesis.
Among the various genotypes (more than 100) the Genotype of HPV which is:

Most commonly associated with squamous cell carcinoma cervix - HPV 16
Most common genotype associated with adenocarcinoma of cervix - HPV 18
Overall MC genotype associated with invasive carcinoma, CIN II and CIN III - HPV 16
But HPV 16 is not very specific as it is seen in 16% of women with low grade lesion and 14% women with normal cytology so: - HPV 18
Most specific genotype of HPV for invasive tumor                                                                           
The cytological changes caused by HPV are collectively called as Koilocytosis.
In most of the females HPV infection clears in 9-15 months , only in small minority it persists.
Malignant transformation requires expression of E6 and E7 HPV oncoproteins.
16 and 18
1 and 33
6 and 11
2 and 14