Recall the log to exponential rule:
[tex]\begin{gathered} If \\ \log_aN=x \\ then \\ a^x=N \end{gathered}[/tex]Therefore, we can express the log expression given to be:
[tex]\log_32187=7[/tex]in the exponential form as:
[tex]3^7=2187[/tex]OPTION A is correct.