Reason for rioters destroying threshing machines in England during the 1830s:

During the 1830s, there were widespread riots in England, known as the "Swing Riots," which mainly targeted the newly introduced threshing machines. The most appropriate reason that exhorted rioters to destroy these machines was that they deprived workmen of their livelihood.

1. Introduction:
The introduction of threshing machines in England during the 1830s brought about significant changes in the agricultural sector. However, it also led to social unrest and protests as many individuals saw their traditional way of life being threatened.

2. Impact on Workmen:
The introduction of threshing machines had a direct impact on the livelihood of workmen, particularly those involved in the manual labor of threshing crops. These machines were capable of automating the process, reducing the need for manual labor, and causing job losses for the workmen.

3. Economic Displacement:
The workmen who relied on manual threshing for their livelihood were suddenly faced with unemployment and economic displacement. They found themselves without a source of income and struggled to find alternative employment opportunities in the changing agricultural landscape.

4. Fear and Frustration:
The fear of economic hardship and frustration due to unemployment fueled the anger and resentment among the workmen. They perceived the introduction of threshing machines as a threat to their traditional way of life and as a means for the landowners to exploit their labor further.

5. Symbol of Resistance:
The threshing machines became a symbol of the economic changes and the perceived injustice inflicted upon the working class. Destroying these machines became an act of resistance and a way for the rioters to express their grievances against the mechanization of agriculture.

6. Revolt against Industrialization:
The riots were not only driven by economic factors but also reflected a broader resistance against the industrialization and modernization of agriculture. The rioters saw the machines as a symbol of the encroachment of industrialization into the rural countryside, threatening their way of life and traditional social structures.

Conclusion:
In conclusion, the most appropriate reason that exhorted rioters to destroy threshing machines in England during the 1830s was that these machines deprived workmen of their livelihood. The introduction of these machines led to unemployment and economic displacement among the workmen, who saw them as a threat to their traditional way of life. The destruction of the threshing machines became a symbol of resistance against the mechanization of agriculture and the broader industrialization that was transforming society during that time.