**Category:** Genetics  
**Subtype:** Mendelian Inheritance  
**Problem Description:** Determine the parental cross that results in a genotype ratio of \(X^{\mathrm{a}}Y\) being 25% in the offspring.

**Summary:** The problem asks which of the given genetic crosses will produce offspring with the genotype \(X^{\mathrm{a}}Y\) at a frequency of 25%.