The docs for Select SubArray in Array say that

• Start Index is The start index of the subarray to return.
• End Index is The end index of the subarray to return.

But the start index is inclusive, while the end index is not.

In standard range notation: [start, end)

That means if start index = 2 and end index = 5, then Select SubArray in Array selects elements 2, 3, and 4 from the input array.