Mendel's Law of Independent Assortment states that:

• A. Alleles for different genes assort independently into gametes.
• B. The two factors for each trait separate into gametes.
• C. One trait is examined in a cross.
• D. DNA is inherited from both parents equally.

Answer: (A)

During formation of gametes, the alleles for different genes can segregate into gametes independently of one another. If two genes are on different chromosomes (or far apart on the same chromosome), the assortment of one gene’s allele into a gamete is independent of the other gene’s allele. This means you can get all possible combinations of alleles in the gametes with roughly equal probability, such as AB, Ab, aB, and ab when considering alleles A/a and B/b. That direct description is exactly what Mendel’s Law of Independent Assortment states.

In contrast, saying that the two factors for each trait separate into gametes describes the segregation of alleles for a single gene (the first law), not the independent behavior of two different genes. Mentioning examining one trait in a cross describes a monohybrid cross, and saying DNA is inherited from both parents equally relates to inheritance in general rather than the specific law about independent assortment.