Final answer:
Option D 'that subjects could identify a card in the dealer's hand by using thought transference' is the most direct and clear choice that maintains the original meaning and enhances readability.
Step-by-step explanation:
To simplify the underlined part of the given sentence we can opt for the choice that makes the sentence most direct and clear. The sentence should maintain its original meaning while enhancing readability.
Among the options provided, option D, 'that subjects could identify a card in the dealer's hand by using thought transference', achieves this by presenting the information succinctly and directly, in an active voice. It clearly indicates that Joseph Banks Rhine claimed statistical proof for the ability of subjects to identify cards using thought transference.