Question

A harrow is used to remove
A. Weeds
B. Crop plants
C. Stones
D. Rocks

Answer 1

Hint: When plants of the same kind are cultivated at one place on a large scale, it is called a crop. Cultivation of crops involves several activities undertaken by farmers over a period of time.
-Preparation of soil
-Sowing
-Adding manure and fertilizers
-Irrigation
-Protecting from weeds
-Harvesting
-Storage

Step by step answer:In a field many other undesirable plants may grow naturally along with the crop. These undesirable plants are called weeds. The removal of weeds is called weeding. Weeding is necessary since weeds compete with the crop plants for water, nutrients, space, and light. Thus, they affect the growth of the crop.
The manual removal includes physical removal of weeds by uprooting or cutting them close to the ground, from time to time. This is done with the help of a khurpi.
A harrow is also used to uproot weeds.
Hence, the correct answer is option A. Weeds

Additional information :
Some weeds interfere even in harvesting and may be poisonous for animals and human beings.
Farmers adopt many ways to remove weeds and control their growth.
Tilling before sowing of crops helps in uprooting and killing of weeds, which may then dry up and get mixed with the soil.
The best time for the removal of weeds is before they produce flowers and seeds.
Weeds are also controlled by using certain chemicals, called weedicides, like 2,4-D. These are sprayed in the fields to kill the weeds. They do not damage the crops. The weedicides are diluted with water to the extent required and sprayed in the fields with a sprayer.

Note: The harrow is used for sowing with the help of tractors. This sows the seeds uniformly at equal distance and depth. It ensures that seeds get covered by the soil after sowing. This protects seeds from being eaten by birds. Sowing by using a seed drill saves time and labor. Appropriate distance between the seeds is necessary to avoid overcrowding of plants. This allows plants to get sufficient sunlight, nutrients and water from the soil. At times a few plants may have to be removed to prevent overcrowding.