Directions: Study the details below and answer the question that follows.

Seven travelers—A, B, C, D, E, F, and G—are seated in a single straight row, all facing North, ready to depart for different destinations: Tokyo, Paris, London, New York, Sydney, Rome, and Cairo. The arrangement of the travelers and their destinations is based on the following conditions:

A sits at one of the extreme ends of the row and visits Paris.
G sits at the other extreme end of the row.
The visitor of New York sits exactly in the middle of the row.
The number of people to the left of B is equal to the number of people to the right of F.
C visits Tokyo and sits to the immediate right of B.
F visits Rome and sits to the immediate left of G, who visits Cairo.
E sits adjacent to F.

If all the travelers are rearranged in alphabetical order from right to left, the positions of how many travelers will remain unchanged?

The correct answer is One.

Step 1: Determine the extreme positions (Ends of the row).
There are 7 seats in a single straight row facing North. Let us number the seats from 1 to 7 from Left to Right:
[Seat 1] [Seat 2] [Seat 3] [Seat 4] [Seat 5] [Seat 6] [Seat 7]

- Condition: A sits at one extreme end, and G sits at the other extreme end.
- Condition: F sits to the immediate left of G.
Since all travelers are facing North, the immediate left of Seat 1 is outside the row. Therefore, G cannot sit at Seat 1.
Thus, G sits at Seat 7 (Right end), F sits at Seat 6 (immediate left of G), and A sits at Seat 1 (Left end).

Step 2: Determine the positions of B and C.
- Condition: The number of people to the left of B is equal to the number of people to the right of F.
F is at Seat 6, so there is exactly 1 person (G at Seat 7) to the right of F.
Therefore, there must be 1 person to the left of B, which means B sits at Seat 2.
- Condition: C visits Tokyo and sits to the immediate right of B.
Since B is at Seat 2, C sits at Seat 3.

Step 3: Determine the positions of E and D.
- Condition: E sits adjacent to F.
F is at Seat 6, so adjacent positions are Seat 5 and Seat 7. Since Seat 7 is occupied by G, E sits at Seat 5.
- Condition: The visitor of New York sits in the middle of the row (Seat 4).
The only remaining unassigned traveler is D, so D sits at Seat 4.

Step 4: Summary of initial seating arrangement (Left to Right).
- Seat 1: A (Paris)
- Seat 2: B
- Seat 3: C (Tokyo)
- Seat 4: D (New York)
- Seat 5: E
- Seat 6: F (Rome)
- Seat 7: G (Cairo)

Step 5: Rearrange in alphabetical order from Right to Left.
Rearranging alphabetically from Right to Left means placing A at Seat 7, B at Seat 6, C at Seat 5, D at Seat 4, E at Seat 3, F at Seat 2, and G at Seat 1:
- Seat 1: G
- Seat 2: F
- Seat 3: E
- Seat 4: D
- Seat 5: C
- Seat 6: B
- Seat 7: A

Step 6: Compare initial and new positions.
- Seat 1: A → G (Changed)
- Seat 2: B → F (Changed)
- Seat 3: C → E (Changed)
- Seat 4: D → D (Unchanged)
- Seat 5: E → C (Changed)
- Seat 6: F → B (Changed)
- Seat 7: G → A (Changed)

Only traveler D at Seat 4 remains in the same position. Therefore, the position of exactly One traveler remains unchanged.