If $A$ is a $3\times 3$ complex matrix with characteristic polynomial $f_A(t)=t^3-2$ then

A

$A$ is not diagonalizable.

B

$A$ has one eigenvalue with corresponding eigenspace that is $1$-dimensional and another eigenvalue with corresponding eigenspace that is $2$-dimensional.

C

$A$ has thee distinct eigenspaces, that are each $1$-dimensional.

D

it is impossible to determine if $A$ is diagonalizable without more information.