The major reason for low agricultural productivity in dry regions of India is option 3 - Dependence on erratic monsoon.

This means that the productivity of agriculture in these regions is heavily reliant on the monsoon season. In dry regions, the availability of water is limited, and farmers rely on rainfall to water their crops. However, the monsoon in these areas is often unpredictable and erratic, with irregular patterns and insufficient rainfall. This irregularity creates challenges for farmers in planning their agricultural activities, leading to low productivity.

Option 1 - Constraints of financial resources, refers to the lack of financial resources as a reason for low agricultural productivity. While this can be a contributing factor, it is not specified as the major reason for low productivity in dry regions.

Option 2 - Rural indebtedness, refers to the amount of debt that farmers in rural areas accumulate. While rural indebtedness can certainly have a negative impact on agriculture, it is not specific to dry regions and cannot be considered as the major reason for low productivity in these areas.

Option 4 - Small size of landholdings, refers to the limited land available for agriculture in dry regions. While this can be a constraint, it is not specified as the major reason for low agricultural productivity in these areas.

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