If you wanted to obtain 100% roan calves, then it si required to cross parents who are homo-zygous (pure lines) for the genes associated with this trait.
<h3>What is a homo-zygous individual?</h3>
A homo-zygous is an individual who has the same gene variants or alleles for a given gene locus.
Conversely, a heterozygous is an individual who has different gene variants or alleles for a given gene locus.
In breeding, pure lines (or purebred) are homo-zygous individuals that may be crossed to obtain the desired trait in the descendence.
Learn more about homo-zygous individuals here:
brainly.com/question/13760394
I believe the answer is a. crossing over
True north is a fixed point on the globe. Magnetic north is quite different. Magnetic north is the direction that a compass needle points to as it aligns with the Earth's magnetic field. ... However, its position is constantly changing, and soon magnetic north and true north will align.
