Using BODMAS and taking out the common powers from the bracket,
we are left with:
6⁷(6-1)6⁸(6-1)
6⁷6⁸(6-1) (6-1)
6¹⁵ x 5 x 5
25 x 6¹⁵

Since the bases of the two sides are not equal, we first equate the bases.
We know  8²=64
Therefore,
64^2x+4  =   8 ^{2( 2x+4)} =   8 ^4x+8
 Now let’s change our original equation:
 8^10x-4= 64^2x+4
 8^10x-4= 8 ^4x+8
Thus, 10x -4 = 4x + 8
6x = 12
x = 2

$ \begin{array}{l}Let\,us\,reduce\,the\,number\,{{54}^{{12}}}\operatorname{int}o\,\,factors\,\,of\,\,3\\{{54}^{{12}}}={{(2\times 27)}^{{12}}}\\={{(2\times 9\times 3)}^{{12}}}\\=\,\,{{(2\times 3\times 3\times 3)}^{{12}}}\\=\,\,({{2}^{{12}}}{{3}^{{12}}}{{3}^{{12}}}{{3}^{{12}}})\\=\,\,{{2}^{{12}}}{{3}^{{36}}}\end{array}$

This is a simple problem.
The number effectively becomes 612 x 10⁷
. All you need to do is place seven zeros after the two.

The numerator reduces to:
2²⁷3⁸7⁶11⁵
Dividing by
2²⁵3⁷7⁶11⁵,
we obtain 2²3¹, thus the correct answer is option D.