Multifactorial inheritance is seen in
High-Yield Explanation
*The multifactorial disorders result from the combined actions of environmental influences and two or more mutant genes.*Some disorders of multifactorial inheritance are cleft lip/palate, congenital hea disease, coronary hea disease, hypeension, gout, diabetes, pyloric stenosis etc.*Note: Most of the congenital diseases are multifactorial. In our question "cardiac septal defect" is the only congenital disease.(Ref: Robbins 7/e p170)