Concept:The part labeled II is the scraper attached to a disc plough. It keeps the disc clean during tillage.
Explanation:The scraper is mounted very close to the surface of the disc.
When the plough works in wet or sticky soil, mud often clings to the disc.
This mud reduces the cutting efficiency of the disc.
The scraper removes this mud as the disc rotates.
It therefore prevents the disc from becoming clogged.
This helps the disc continue to cut the soil properly.
Answer:D. removes mud that clings to the disc
