Concept:A tractor-mounted sprayer must be capable of covering a large area efficiently.
Explanation:A boom sprayer has a long horizontal boom fitted with many nozzles.
It can spray a wide swath in a single pass.
It is commonly attached to a tractor on large farms.
This makes it suitable for large-scale farming operations.
Knapsack sprayers are carried on the back and are used on small farms.
Electrodyne and motorised sprayers are not ideal for large-scale farm coverage.
So, the best choice is the boom sprayer.
Answer:B. Boom sprayer