The correct answer is (a) Section 329.
Section 329 of the Indian Penal Code deals with voluntarily causing grievous hurt. It states that whoever voluntarily causes grievous hurt to any person, shall be punished with imprisonment for life, or with imprisonment of either description for a term which may extend to ten years, and shall also be liable to fine.
In the given case, A, a Zamindar, tortures a raiyat in order to compel him to pay his rent. This clearly amounts to voluntarily causing grievous hurt to the raiyat. Therefore, A is guilty of an offence under Section 329 of the Indian Penal Code.
The other options are incorrect because they do not deal with the specific offence that A has committed. Section 333 deals with voluntarily causing hurt by dangerous weapons or means. Section 330 deals with voluntarily causing hurt to extort property, or to compel a person to do an act against his will. Section 331 deals with voluntarily causing hurt to deter a public servant from his duty.
In conclusion, A is guilty of an offence under Section 329 of the Indian Penal Code for voluntarily causing grievous hurt to the raiyat.