The correct answer is 9.

Section 2 of the Dissolution of Muslim Marriage Act, 1939 deals with grounds for decree for dissolution of marriage.

A woman married under Muslim law is entitled to obtain a decree for the dissolution of her marriage on any one or more of the following grounds: husband's whereabouts unknown for four years; failure to provide maintenance for two years; husband sentenced to imprisonment for seven years or more; failure to perform marital obligations for three years; husband's impotence at time of marriage; husband's insanity for two years or virulent venereal disease; repudiation of marriage before age eighteen when married before fifteen (provided marriage not consummated); cruelty by husband; or any other ground recognised as valid under Muslim law.