Deciduous trees are those that lose their leaves annually.

Option 1 only one: This answer is incorrect. More than one of the listed trees are deciduous.

Option 2 only two: This is the correct answer. Mahua (Madhuca indica) and Teak (Tectona grandis) are both deciduous trees. They shed their leaves during the dry season and grow new leaves during the rainy season.

Option 3 all three: This answer is incorrect. While Mahua and Teak are deciduous, the Jackfruit tree (Artocarpus heterophyllus) is not a deciduous tree. It`s an evergreen tree, which means it retains its leaves throughout the year.

Option 4 none: This answer is also incorrect as two out of the three trees listed are deciduous.

Hence, the correct answer is ‘only two’ i.e., Mahua and Teak are deciduous.