C. 9 x 9 x 9 x 9 x 9 is equivalent to 9⁵
Exponential form : It is an easier way to write repeated multiplication of a number or variable using base(number or variable) and exponents.
Example : 6⁵ is the exponential form of 6×6×6×6×6 (i.e. 5times)
Here, given expression is 9⁵
So, in this expression, 9 multiplied 5 times, i.e. 9×9×9×9×9
Learn more about exponential form here :
https://brainly.com/question/14640920
#SPJ2