The correct answer is: a) Tea plantations.
The Assam Agricultural Income Tax Act, 1982 is an Act to provide for the levy and collection of agricultural income tax in the State of Assam. The Act applies to income from agricultural land situated in the State of Assam.
Agricultural income means income derived from any land used for agricultural purposes, including income from the cultivation of tea, coffee, rubber, cardamom, ginger, turmeric, chillies, tobacco, sugarcane, oilseeds, fruits, vegetables, flowers, and other horticultural crops.
Tea plantations are a major source of agricultural income in Assam. The Act provides for a number of exemptions and deductions in respect of agricultural income. The Act also provides for a number of penalties for contravention of its provisions.
The other options are incorrect because they are not included in the definition of agricultural income under the Act.