SSC CGL 2025 Tier-I · 16 September 2025, Shift 1 · General Intelligence and Reasoning · Question 4 of 100

We transcribed this text from the pictures on a candidate's response sheet for this shift; the answer is the key SSC colour-marked on that sheet. Solution last reviewed 13 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. From 2025 the candidate response sheet prints every question and option as a picture, so the text here is transcribed from those pictures for this shift and checked against them independently; where the layout carries meaning, the picture is shown as well. Each answer is the key SSC colour-marked on that sheet. SSC released a tentative key for challenge and later its final one, both only to candidates behind a login, and the sheet does not say which of the two it carries. The solutions are written by UnlockIAS.

Select the letter-cluster from among the given options that can replace the question mark (?) in the following series: GBDF, GHMR, GNVD, GTEP, ?

(a)G Z M B
(b)G Z N C
(c)G Z N B
(d)G Y N B

Answer

Why

Correct — C.
Rule: G never moves; the 2nd, 3rd and 4th letters move +6, +9, +12, wrapping past Z back to A.

2nd: B, H, N, T → T + 6 = Z
3rd: D, M, V, E → E + 9 = N
4th: F, R, D, P → P + 12 = 28 − 26 = B

G Z N B → option (c).

Why the others are wrong

(a)
G Z M B — M is E + 8. The 3rd letter moves +9 each time (D, M, V, E), so after E comes N.
(b)
G Z N C — C is P + 13. The 4th letter moves +12 each time (F, R, D, P), so P + 12 = 28 − 26 = 2, which is B.
(d)
G Y N B — Y is T + 5. The 2nd letter moves +6 each time (B, H, N, T), so after T comes Z.

Concept

A letter-cluster series is several series running side by side. Read each position down the terms on its own and find its step.

Here the 1st letter is fixed at G. The others step +6, +9 and +12. When a sum passes 26, subtract 26 to wrap from Z back to A: V(22) + 9 = 31 → 5 = E, and R(18) + 12 = 30 → 4 = D.

Each wrong option differs from G Z N B in a single letter, so each one tests a different moving position.

Key facts

Position anchors: E = 5, J = 10, O = 15, T = 20, Y = 25.
Past Z, subtract 26: P(16) + 12 = 28 → 2 = B.
The steps here are +6, +9 and +12 for the 2nd, 3rd and 4th letters.

Study next

Letter-cluster series with backward stepsLetter-cluster series where one position stays fixedWrap-around arithmetic on letter positions

Common traps

Forgetting to wrap past Z: R + 12 = 30 must become 4, which is D
Checking the 2nd letter only, where options (a), (b) and (c) all show Z

14 Sep 2025, 09:00, Reasoning Q.6 (TDGJ, TGMS, TJSB, TMYK) keeps T fixed and moves the other letters +3, +6, +9.

15 Sep 2025, 16:00, Reasoning Q.6 (PCHJ, PGPV, PKXH, POFT) keeps P fixed with steps of +4, +8, +12.

Related PYQs

No directly related past PYQ was found.

Topic: Semantic Series — all 125 SSC CGL questions on it, every solved shift.