Which of the Following Was NOT Proposed in the Preface

Which of the following was NOT proposed in the Preface of Wundt's early textbook,Contributions to the Theory of Perception,where he described the program that would occupy him for the rest of his life?

A) an experimental psychology to introspectively study the facts of consciousness
B) a psychology for studying the higher mental functions based on historical, comparative, and ethnographic analyses
C) a psychology of individual differences, applying facts of general psychology toward an understanding of single personalities
D) the systematic study of reaction times