[Solved] Which of the following body areas has (have) the greatest degree of representation on the primary motor cortex and the somatosensory cortex? A)the knee B)the face C)the arm D)the feet Erotic Plasticity: The degree to which an individual's sex drive can be changed by social, environmental, and situational factors. Fraternal Birth-Order Effect: The observation that a man is more likely to be homosexual the more older brothers he has from the same mother. Older Brothers: Typically refers to male siblings who are born before other children in a family, often associated with roles of protection, mentorship, and influence in the sibling relationship. Prenatal Development: Prenatal development refers to the process of growth and development within the womb from conception to birth.