Read the following passage and answer the item that follows. Your answer to this item should be based on the passage only.

Compared to other agrarian economies, India's shift out of subsistence farming has been slow, weighed down by the fact that most of its farms remain small and fragmented. Yet even within this constraint, when relative prices moved in favour of horticulture and livestock over the last decade, private investment in these sub-sectors rose sharply, farm incomes in affected regions grew faster, and rural non-farm employment expanded alongside it.

With reference to the above passage, the following assumptions have been made:

1. Structural transformation of agriculture is impossible while farms remain small and fragmented.

2. A favourable shift in relative prices can trigger higher private investment in agriculture.

3. Building stronger value chains for horticulture and livestock would help sustain such income gains.

4. Higher global commodity prices are essential for India's rural income growth.

Which of the above assumptions are valid?