kaplan CAT - SC

avik.ch wrote:Although still a matter of dispute, most historians agree that the Russian monk Rasputin charmed the Czarina into believing by the laying on of hands to be able to heal her son's hemophilia.
A. by the laying on of hands to be able to heal ----- awkward
B. by the laying on of hands that he can heal ----- awkward
C. his ability, by the laying on of hands, ofhealing ---- ability to is the right idiom
D. that he could, by the laying on of hands, heal ---- by the laying on of hands is just extra information
E. his being able to heal, by the laying on of hands,

The OA is D. Can someone please explain me this SC