Being born right-handed confers a survival advantage. Forcing a person to switch from a preferred hand is harmless. Societal attitudes toward handedness differ at different times. Handedness is a product of both genetic predisposition and social pressures.
M: It is almost impossible to find a person between the ages of 85 and 90 who primarily uses the left hand. Q: Seventy to ninety years ago, however, children were punished for using their left hands to eat or to write and were forced to use their right hands.
Q's response serves to counter any use by M of the evidence about 85 to 90 year olds in support of which one of the following hypotheses?