​Doubled haploids (DH) are plants derived from single immature pollen and doubled artificially to form diploids. A DH population was created from F₁ progeny derived from a cross between two parents (P1 and P2), one resistant (R) and the other sensitive (S) to white rust. The parents, F₁, and DH population were profiled with a set of co-dominant markers, which is represented below.

​The following table summarizes the proposed percentage of the 4 different types (1 to 4) of DH progeny, assuming that the DNA marker is (i) unlinked to the gene governing the trait and (ii) linked at a distance of 10 cM.​

​Which one of the following options correctly represents the expected ratio for unlinked and linked, respectively?​

Correct option is B

Step-by-Step Explanation:
The Table from Image 1:

This table provides the expected percentage of progeny with four profiles (1 to 4) for two scenarios:

Unlinked: When the DNA marker is unlinked to the gene controlling the trait.

Linked (10 cM): When the DNA marker is linked to the gene controlling the trait at a distance of 10 cM.

The values for these two scenarios are proposed for two different genetic scenarios (A and B) that describe the proportions of the four profiles of DH progeny.

Interpretation of the Answer Options:
Option A: A, ii

This suggests that for "Unlinked" and "Linked" markers, the expected percentages are as given in Scenario A for unlinked and Scenario ii for linked.

Option B: A, i
​
This suggests that the expected progeny percentages for Scenario A for unlinked markers and Scenario i for linked markers.
​
Option C: B, i
​
This suggests that the expected progeny percentages are from Scenario B for unlinked markers and Scenario i for linked markers.

Option D: A, iii

This suggests that the expected progeny percentages are from Scenario A for unlinked markers and Scenario iii for linked markers.

Correct Answer:
The correct answer is Option B (A, i).