A.  [digits][.digits][(E|e)[(+|-)]digits].

B.  [digits][+digits][(E|e)[(+|-)]digits].

C.  [digits][(E|e)[(+|-)]digits].

D.  [.digits][digits][(E|e)[(+|-)]digits].

Correct Answer :
[digits][.digits][(E|e)[(+|-)]digits].
Explanation :

Floating-point literals may also be represented using exponential notation: a real number followed by the letter e (or E), followed by an optional plus or minus sign, followed by an integer exponent. This notation represents the real number multiplied by 10 to the power of the exponent.


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