Explanation:

- To solve the question, look for pairs of letters in "BACKGROUND" that have the same number of letters between them in the word as in the English alphabet, both forward and backward.

- Let's write the letters with their positions:

B(1) A(2) C(3) K(4) G(5) R(6) O(7) U(8) N(9) D(10)

- Now, check for such pairs:

- B – A: No letter between, but in alphabet B and A have no letter between.

- B – C: One letter between in the word (A). In alphabet, B and C have no letter between.

- C – K: From C (3) to K (4): One letter between (K), but in alphabet, C and K have 7 letters between.

- G – N: G(5), N(9), letters between: R,O,U (positions 6-8), three letters. In alphabet, G to N: H,I,J,K,L,M (6 letters between).

- R – U: R(6), U(8), one letter between (O). In alphabet, R to U: S,T (two letters).

- U – N: U(8), N(9), no letter between in the word. Alphabetically U to N is backward, N to U is 6 letters.

- In "BACKGROUND", after checking all possible pairs, only one pair fulfills the criteria: B and A (no letter between them in both word and alphabet).

- Let's verify backward pairs:

- D(10) – N(9): No letter between in the word, but alphabetically N and D are apart by nine letters.

- None match except B and A.

Highlighting the correct answer:

Option:1, One