#### Answer

c.

#### Work Step by Step

We are studying the following pattern: $a^2$#$a^4 = a^{10}$, $a^3$#$a^2=a^7$, $a^5$#$a^3 = a^{11}$
We know it's not equation a.
because $a^{2*2+4} \ne a^{10}$
We know it's not equation c.
because $a^{3+2+4}\ne a^7$
We know it's not equation d.
because $a^{5*3+2}\ne a^{11}$
Therefore, it has to be equation c.