which of the following ecosystems has highest productivity

1. tropical deciduous forest
2. temperate coniferous forest
3. tropical rain forest
4. desert shrub

Tropical rain forest has the highest productivity.
A tropical rainforest is an ecosystem type that occurs roughly within the latitudes 28 degrees north or south of the equator. This ecosystem experiences high average temperatures and a significant amount of rainfall. Rainforests can be found in Asia, Australia, Africa, South America, Central America, Mexico and on many of the Pacific, Caribbean, and Indian Ocean islands. Within the World Wildlife Fund's biome classification, tropical rainforests are thought to be a type of tropical wet forest (or tropical moist broadleaf forest) and may also be referred to as lowland equatorial evergreen rainforest.