To improve the shelf life of horticultural produce, Assam promotes:

Processing and value addition
Pre-cooling techniques
Refrigerated transport
All of the above

The correct answer is: d) All of the above.

Processing and value addition: This involves converting fresh produce into other products, such as canned fruits and vegetables, juices, and jams. This can help to extend the shelf life of produce and make it more marketable.

Pre-cooling techniques: This involves cooling produce as soon as possible after harvesting. This can help to reduce the rate of spoilage and extend the shelf life of produce.

Refrigerated transport: This involves transporting produce at a low temperature. This can help to reduce the rate of spoilage and extend the shelf life of produce.

All of these methods can help to improve the shelf life of horticultural produce and reduce post-harvest losses.