Is has been said that to be afraid of the dark is being afraid of all those things we cannot comprehend and, therefore, instinctively fear.

(A) said that to be afraid of the dark is being afraid
(B) said, that to be afraid of the dark, is being afraid
(C) said being afraid of the dark is to be afraid
(D) siad that to be afraid of the dark is to be afraid
(E) said that to be being afraid of the dark is to be being afraid

IMO Answer (D).

Going by the meaning of the sentence we can say that it is saying "One thing has been said ..(something).. is ..(something).. .". So if a draw an analogy that what was in past remains as it is in present, only options(D) matches it.

Also 'said' has to be followed by 'that' so option (C) is out. (E) is redundant for using 'to be' and 'being' together.
Option (B) and (A) are similar to each other only that (B) uses comma after 'said' and 'dark' but the bigger problem lies in using 'being'.
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Hope it helps
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