Bee-keeping is suitable as an additional income because it:

The correct option is Requires low investment.

Bee-keeping (apiculture) is considered an ideal subsidiary or additional income-generating activity for rural farmers and entrepreneurs due to several key reasons:

1. Low Capital Investment: Setting up a bee-keeping unit requires minimal initial cost. Equipment like beehives, frames, and protective gear are relatively inexpensive and can easily be sourced or built locally.

2. Low Maintenance and Space Requirements: It requires very little physical land and negligible recurring maintenance expenses, as bees naturally collect nectar and pollen from surrounding flora.

3. Additional Yields: Besides producing honey, bee-keeping yields valuable by-products such as beeswax, royal jelly, and propolis, which have significant commercial value in pharmaceutical and cosmetic industries.

4. Agricultural Benefit: Honeybees act as major pollinators, which helps in increasing the crop yield of neighboring agricultural fields.

Therefore, bee-keeping is highly suitable as an additional source of income because it requires low investment.