Which of the Following Describes Wundt's Use of Introspection as an Experimental

Which of the following describes Wundt's use of introspection as an experimental technique?

A) The participants in his study focused on internal thoughts and feelings about their competence while performing a task.
B) The participants in his study drew from their internal thoughts and feelings as they described an object in detail.
C) The participants in his study pressed a telegraph key as soon as they heard a ball drop onto a platform,indicating their internal state.
D) The participants in his study used mental building block constructs to describe their perception of an object.