Horticulture in Mizoram is often practiced on:

The correct answer is: a) Hill slopes and terraces.

Horticulture is the practice of cultivating plants for food, ornamental, or medicinal purposes. It is often practiced on hill slopes and terraces because these areas are well-suited for growing crops. Hill slopes provide good drainage and sunlight, while terraces help to prevent soil erosion.

Vast plains are not ideal for horticulture because they are often flat and have poor drainage. Coastal areas are also not ideal for horticulture because they are often salty and have high winds. Urban rooftops are not ideal for horticulture because they are often small and have poor soil quality.

Here are some additional details about each option:

• Hill slopes and terraces are well-suited for growing crops because they provide good drainage and sunlight. Hill slopes also help to prevent soil erosion.
• Vast plains are often flat and have poor drainage. This makes them less suitable for growing crops.
• Coastal areas are often salty and have high winds. This makes them less suitable for growing crops.
• Urban rooftops are often small and have poor soil quality. This makes them less suitable for growing crops.