Suppose that new high-technology farming equipment is developed. These new machines are substitutes for low-income workers such as farm laborers, but they are complements for high-income workers such as farm technicians and farm owners. This new technology will shift the demand curve for low-income workers to the while shifting the demand curve for high-income workers to the .

A. left : left
B. right : left
C. left : right
D. right : right

If a new machine subsituites for low income workers, less of low income workers would be demanded. Therefore the demand curve for low income workers would shift to the left.

If the machine can be substituted for low income workers, it means it can be used instesd of low income workers.

If a new machine complements high income workers, the demand for high income workers would increase and the demand curve of high income workers would shift to the right.

If the new machine complements high income workers, it means it can be used with high income workers.

I hope my answer helps you