What is the solution to the inequality below?

square root of x < 16

a. x < 256
b. 0 is less than or equal to x is less than 256
c. x < 4
d. no solutions

The answer is:  [A]:  x < 256 .
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Explanation:
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Given:
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  <  16  ;
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We simplify "x" by "squaring" (that is, raising EACH SIDE to the second power); 
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→   () ²   <  16 ² ;
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to get:
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→  x  <  256 ;  which is "Answer choice: [A]: x < 256 " .
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Where’s the