How many letters will remain unchanged if the word EDUCATION is arranged alphabetically?

The correct answer is Zero.

Let's analyze the position of each letter in the original word and compare it with the positions after rearranging the letters in alphabetical order.

Step 1: Write down the original word and note the position of each letter.
Original Word: E D U C A T I O N

Position 1: E
Position 2: D
Position 3: U
Position 4: C
Position 5: A
Position 6: T
Position 7: I
Position 8: O
Position 9: N

Step 2: Arrange all the letters of the word alphabetically.
Alphabetical Order: A C D E I N O T U

Step 3: Compare the original positions with the new positions:

Position 1: E → A (Changed)
Position 2: D → C (Changed)
Position 3: U → D (Changed)
Position 4: C → E (Changed)
Position 5: A → I (Changed)
Position 6: T → N (Changed)
Position 7: I → O (Changed)
Position 8: O → T (Changed)
Position 9: N → U (Changed)

As we can see, none of the letters remain in the exact same position after being arranged alphabetically. Therefore, the number of unchanged letters is Zero.