In the following letter sequence, one term is missing. Choose the correct option that will replace the question mark. EV, GT, JQ, OL,?

Correct — A.
Rule: each term is a letter and its opposite, whose positions add to 27, and the first letters step +2, +3, +5, +7.

First letters: E(5) → G(7) → J(10) → O(15), steps +2, +3, +5.
Next step +7: 15 + 7 = 22 = V.

Second letters are the opposites: E–V, G–T, J–Q, O–L each add to 27.
Opposite of V: 27 − 22 = 5 = E, so the term is VE → option (a).

Why the others are wrong

• (b)
  RI — RI is an opposite pair (18 + 9 = 27), but R is O + 3. The steps have grown +2, +3, +5, so the next cannot drop back to +3.
• (c)
  KP — KP is an opposite pair (11 + 16 = 27), but K is O − 4. The first letters have only moved forward, so a step back breaks the series.
• (d)
  UF — UF is an opposite pair (21 + 6 = 27), but U is O + 6. After +2, +3 and +5 the next prime step is +7, which gives V.

This letter-pair series runs two rules, one per letter. Number the letters (A = 1 to Z = 26) and read each column on its own.

Opposite letters sit the same distance from the two ends of the alphabet, as A–Z, B–Y and E–V do, and their positions always add to 27. When every term is an opposite pair, find the first letter and the second follows.

Key facts

• Opposite letters add to 27: E(5)–V(22), G(7)–T(20), J(10)–Q(17), O(15)–L(12).
• The first letters step +2, +3, +5, +7, the primes in order.
• The second letters fall by the same steps: V, T, Q, L, then E.

Common traps

• Stopping at the opposite-pair check, which all four options pass
• Treating the step as fixed, when it grows 2, 3, 5 and then 7

No directly related past PYQ was found.