question_answer

If \[{{\left( \frac{5}{9} \right)}^{4}}\times {{\left( \frac{5}{9} \right)}^{-10}}={{\left( \frac{5}{9} \right)}^{-4}}{{\left( \frac{5}{9} \right)}^{2a-1}},\]then the value of a is _____.

A)  1                                

B)  \[\frac{-5}{2}\]                     

C)  \[\frac{-5}{4}\]                     

D)         \[\frac{-1}{2}\]