Section 25 declares that a marriage shall voidable and may be annulled by a decree of nullity if, "(i) the marriage has not been consummated owing to the 712 wilful refusal of the respondent to consummate the marriage; or (ii) the respondent was at the time of the marriage pregnant by some person other than the petitioner; or (iii)the consent of either party to the marriage was obtained by coercion or fraud, as defined in the ." (The provisos have been omitted as they are not necessary for the purposes of this case) Section 27 enables either the husband or the wife to seek a decree of divorce on the ground that the respondent "(a) has, after the solemnization of the marriage, had voluntary sexual intercourse with any person other than his or her spouse; or (b) has since the solemnization of the marriage treated the petitioner with two years immediately preceding the presentation of the petition; or (c) is undergoing a sentence of imprisonment for seven years or more for an offence as defined in the Indian Penal Code; (d) has since the solemnization of the marriage treated the petitioner with cruelty; or (e) has been incurably of unsound mind, or has been suffering continuously or intermittently from mental disorder of such a kind and to such an extent that the petitioner cannot reasonably be expected to live with the respondent.