In pedigree analysis, a male patient with a genetic disease has parents and grandparents who are normal, one uncle is also normal, but the other uncle suffers from the same disease. Determine the mode of inheritance for this genetic disease.
Correct answer: B. autosomal recessive
The presence of the disease in one uncle and not in the other suggests that the affected gene is on an autosome. The fact that both parents are normal but their son has the disease indicates that it is a recessive trait.