Explanation:

- U is a prime-numbered box: Possible positions for U are 2, 3, or 7 (since 5 is excluded).

- Number of boxes above W equals number below U: This means W is at position 2 and U at position 3.

- Box S is twice the position of box V: Possible pairs (S, V) are (2, 1), (4, 2), and (6, 3); valid here is (4, 2) or (6, 3).

- P is just above U: P is at position 4.

- Q is two boxes above T: With the current setup, Q is at position 7 and T at 5.

Sorting all, we have:

1. V

2. W

3. U

4. S

5. T

6. P

7. Q

8. R

Thus, the bottommost box is V.

The correct answer is Option: 4 - V.

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