In a certain code language, ‘TERRAIN’ is written as ‘VETTAIP’ and ‘TRAFFIC’ is written as ‘VTAHHIE’. How will ‘MOTOR’ be written in that language?

Correct — C. Rule: every consonant moves +2 places in the alphabet; every vowel stays exactly where it is.

TERRAIN: T→V, E→E, R→T, R→T, A→A, I→I, N→P = VETTAIP.
TRAFFIC: T→V, R→T, A→A, F→H, F→H, I→I, C→E = VTAHHIE.

Now MOTOR: M→O, O→O, T→V, O→O, R→T.

That reads OOVOT, option (c).

Why the others are wrong

• (a)
  OVOTO — OVOTO puts V in slot 2, but slot 2 of MOTOR holds the vowel O, and the rule leaves every vowel untouched.
• (b)
  VOOOT — VOOOT opens with V, which is the code for T. The first letter is M, and M + 2 = O, so the code must begin with O.
• (d)
  OOTVO — OOTVO leaves T sitting in slot 3. T is a consonant, so it has to become V — only the vowels survive unchanged.

Letter-coding items hide the rule in the exceptions. Six of the seven letters of TERRAIN move, and the three that refuse to move — E, A, I — are exactly its vowels.

So the moment one letter codes to itself, test the vowel-consonant split before anything else.

Write the plain word above its code, letter under letter, and mark each pair with its shift. A column of +2s broken only by zeros at the vowels is the whole answer.

Key facts

• T→V, R→T, N→P and C→E are all +2 steps in the English alphabet.
• A, E and I code to themselves in both given words.
• MOTOR carries vowels in positions 2 and 4, so its code carries O in positions 2 and 4.

Common traps

• Shifting the vowels too, which turns MOTOR into OQVQT
• Reading the shift off the first letter alone and assuming every letter moves the same way
• Reordering the coded letters when the code preserves the original order

No directly related past PYQ was found.