Select the combination of letters that when sequentially placed in the blanks of the given series will logically complete the series. BYN_J_YNF_X_NFJVY_FJ

Correct — B.

The string is twenty characters long, so split it into blocks of five:

BYN_J | _YNF_ | X_NFJ | VY_FJ

Rule: in every block, positions 2 to 5 read Y N F J. Only the first letter of a block changes.

Now read the blanks in order. The first is position 4 of block 1, so F. The second is the free first letter of block 2. The third closes block 2, so J. The fourth is position 2 of block 3, so Y. The fifth is position 3 of block 4, so N.

That fixes the answer as F, then a free letter, then J, Y, N. Option (b) reads FZJYN, and its Z completes the leading letters B, Z, X, V, which step back two at a time once the alphabet wraps → option (b).

Why the others are wrong

• (a)
  FJZNY — FJZNY breaks from the second blank on. That blank is the leading letter of block 2, which must be Z, and the third blank closes block 2, where the tail Y N F J calls for J and the option supplies Z.
• (c)
  FZYVJ — FZYVJ puts Y in the third blank, where block 2 must end in J. Its last two letters miss as well — block 3 needs Y where it writes V, and block 4 needs N where it writes J.
• (d)
  FNJYV — FNJYV fails twice. Its second letter N sits in the leading column, which must read B, Z, X, V; and block 4 needs N in its third position, where the option ends with V.

A letter series with blanks is solved by finding the period first, not by filling gaps left to right. Count the characters, look for a repeated run, then write the string out in rows of that length.

Here the period is five and the run YNFJ repeats down four of the five columns. Once the string is in rows, four of the five blanks are read straight off the columns above and below them.

The remaining blank is the first column, which holds B, Z, X, V. That column steps back two letters at a time, wrapping from B round to Z.

Key facts

• Written in fives the string is BYN_J, _YNF_, X_NFJ, VY_FJ.
• Columns 2 to 5 hold Y, N, F and J in every row.
• The first column reads B, Z, X, V, stepping back two letters at a time.
• The blanks fall at block 1 position 4, block 2 positions 1 and 5, block 3 position 2 and block 4 position 3.

Common traps

• Filling the blanks left to right by ear instead of finding the period first.
• Miscounting the characters and splitting the string into fours or sixes.
• Assuming every blank belongs to the same column of the pattern.

No directly related past PYQ was found.