Which statement best describes the roles of the base and exponent in the notation $5^4$?

$4$ is the base and $5$ is the exponent. $4$ is multiplied by itself $5$ times.

$5$ is the base and $4$ is the exponent. It is a product of four fives.

$5$ is the exponent and $4$ is the base. $5$ is the factor that is repeated $4$ times.

$5$ is the coefficient and $4$ is the exponent. The expression equals $5\cdot 4$.