The farm machinery used to sow seeds and apply fertilizer at the same time is
Answer Details
In agriculture, a harrow (often called a set of harrows in a plurale tantum sense) is an implement for breaking up and smoothing out the surface of the soil. In this way it is distinct in its effect from the plough, which is used for deeper tillage. The farm machinery used to sow seeds and apply fertilizer at the same time is a harrow. Therefore, choice D is correct.