Find which option is not equivalent to
.
Option A :
.
Pythagorean identity :
.

.
Option B :
.
Pythagorean identity :
.

.
Option C :
.
Quotient identity :
.

.
Option D :
.
Quotient identity :
.

Reciprocal identity :
.


Thus, option D is not equivalent to 
Option D is the correct choice.