Question

this passage describes the marfan syndrome trait in humans:
marfan syndrome is a condition that affects a protein called fibrillin. fibrillin helps support many parts of the human body and also affects growth. humans with marfan syndrome tend to be taller than average and have long limbs, fingers, and toes. they may also have heart problems and other organ issues.
in a group of humans, some individuals have marfan syndrome and others do not. in this group, the gene for the marfan syndrome trait has two alleles. the allele for having marfan syndrome (m) is dominant over the allele for not having marfan syndrome (m).
the punnett square below shows a cross between two humans. consider the genotypes of the offspring shown. select all the boxes that represent offspring with a homozygous genotype.

Explanation:

A homozygous genotype has two identical alleles. In the Punnett square, the "mm" genotypes have two identical recessive alleles. The "Mm" genotypes have one dominant and one recessive allele (heterozygous).

Answer:

The boxes with the "mm" genotypes.