Please take a look at the picture
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[tex]\implies {\blue {\boxed {\boxed {\purple {\sf {C.\:None\:of\:the\:above.}}}}}}[/tex] ✔
[tex]\:\large{\boxed{\frak{ Step-by-step\:explanation: }}}[/tex]
A. [tex]x - ( - x) = -x[/tex]
Let us first solve for L. H. S.
We have,
[tex]x - ( - x)[/tex]
[tex] = x + x[/tex]
[tex] = 2x[/tex]
[tex]≠ - x[/tex]
[tex]≠ R. H. S. [/tex]
Hence, option A is incorrect.
B. [tex]0 - ( - x) = - x[/tex]
Solving for L.H.S. , we have
[tex] = 0 - ( - x)[/tex]
[tex] = + x[/tex]
[tex]≠ - x[/tex]
[tex]≠ R. H. S. [/tex]
Hence, option B is ruled out too.
Therefore, the correct answer is [tex]\sf\red{ option\:C}[/tex].