Which one of the following options represents the most appropriate match between all terms of column A and B
(1) A-(ii), B-(iv), C-(i), D-(iii)
(2) A-(iii), B-(i), C-(iv), D-(ii)
(3) A-(iv),B-(iii), C-(iv), D-(i)
(4) A-(iii), B-(iv), C-(i), D-(ii)

Column A vs Column B

Column A:
A. Bulk segregant analysis
B. NILs (Near isogenic lines)
C. Association mapping
D. SNPs

Column B:
(i) QTL analysis of wider genetic diversity using fewer individuals
(ii) Mapping monogenic qualitative traits
(iii) Co-dominant markers
(iv) Repeated backcrossing of F1 to recurrent parent

Correct matches:

• A → (i)

• B → (iv)

• C → (ii)

• D → (iii)

So the full pattern is A–iv, B–iii, C–ii, D–i in option notation.

Why each match is correct

• A. Bulk segregant analysis → (i) QTL analysis of wider genetic diversity using fewer individuals

  • BSA pools DNA from individuals with extreme phenotypes and compares marker frequencies between bulks, allowing QTL detection using relatively few individuals.​

• B. NILs → (iv) Repeated backcrossing of F1 to recurrent parent

  • Near isogenic lines are created by repeatedly backcrossing F1 and later generations to a recurrent parent, selecting for a donor segment each generation.​

• C. Association mapping → (ii) Mapping monogenic qualitative traits

  • Association (linkage disequilibrium) mapping is well suited to detect loci controlling qualitative traits based on marker–trait associations in diverse germplasm.​

• D. SNPs → (iii) Co-dominant markers

  • Single nucleotide polymorphisms are codominant markers, as heterozygotes can be distinguished from both homozygotes by genotyping.​

Thus the option that lists these correctly is:

• (3) A–iv, B–iii, C–ii, D–i.