The whole truth or the real truth

[happyfay]

Test No. incompl/elem-1 "Speaking already", question 8

I want you to tell me the ......... truth.

(a) all
(b) exact
(c) real
(d) whole

Test No. incompl/elem-1 "Speaking already", answer 8

I want you to tell me the whole truth.

Correct answer: (d) whole

Your answer was: incorrect
I want you to tell me the real truth.
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why couldn't we say "real truth" here?

[Alan]

Real doesn't make sense here because you cannot qualify truth as being real.
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English as a Second Language
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