तुमच्या डावीकडून सुरुवात करून जर प्रत्येक एक सोडून एका जोडीतील अक्षरांच्या स्थानांची अदलाबदल पुढे दिलेल्या मालिकेत केली तर कोणते अक्षर अशा अक्षराच्या डावीकडून सातवे येईल जे तुमच्या उजवीकडून तेरावे आहे ?
ETHKWDSBUMCXJANRVOYILPZGQF

The correct answer is Option C (S).

Key Points:
• Given original sequence of 26 letters:
• E T H K W D S B U M C X J A N R V O Y I L P Z G Q F
• Pairing adjacent letters from left: (ET), (HK), (WD), (SB), (UM), (CX), (JA), (NR), (VO), (YI), (LP), (ZG), (QF).
• Interchange every alternative pair starting from left (i.e. pairs 1, 3, 5, 7, 9, 11, 13):
• Pair 1 (ET) -> TE
• Pair 2 (HK) stays HK
• Pair 3 (WD) -> DW
• Pair 4 (SB) stays SB
• Pair 5 (UM) -> MU
• Pair 6 (CX) stays CX
• Pair 7 (JA) -> AJ
• Pair 8 (NR) stays NR
• Pair 9 (VO) -> OV
• Pair 10 (YI) stays YI
• Pair 11 (LP) -> PL
• Pair 12 (ZG) stays ZG
• Pair 13 (QF) -> FQ
• The new sequence is:
• T E H K D W S B M U C X A J N R O V Y I P L Z G F Q
• Target position: 7th to the left of the letter 13th from the right.
• Total letters = 26.
• 13th from right = (26 - 13 + 1) = 14th from left.
• 7th to the left of the 14th letter from left = (14 - 7) = 7th letter from left.
• The 7th letter in the new sequence is S (1: T, 2:E, 3:H, 4:K, 5:D, 6:W, 7:S).
• Hence, the letter is S, matching Option (3).
• Key Takeaway: Reversing alternate letter pairs yields 'S' at the 7th position from the left (7th left of 13th from right).