Interleaved letter streams (−5 and +5): Y, B, T, G, O, ? Find the next letter by separating odd and even positions into distinct progressions.

Introduction / Context:
Here the sequence alternates between two simple arithmetic rules on alphabet positions. By pulling apart odd and even terms, we can extend each subsequence independently and then recombine to get the next letter.

Given Data / Assumptions:

• Series: Y, B, T, G, O, ?
• Alphabet index: A=1 to Z=26.
• Assume two interleaved progressions (odd vs even positions).

Concept / Approach:
Compute positions of letters in odd slots (1,3,5,…) and even slots (2,4,6,…). Identify a constant increment/decrement in each stream and extend the appropriate one for the next term (here, the 6th term).

Step-by-Step Solution:

Verification / Alternative check:

Why Other Options Are Wrong:

• N, M, K do not match the +5 even-position rule from B→G→L.

Common Pitfalls:
Mixing the two interleaved sequences, or trying to apply one rule to the entire list instead of splitting by parity of positions.

Final Answer:
L