I'm getting option b ..according to diagonalization theorem 1st we have to find the eigen value of the given matrix it says that if there are exactly n distinct eigenvalues in an n×n matrix then this matrix is diagonalizable...if eigen values repeated then we have to find the corresponding eigen vector..
a)here getting two eigen values 2 and 1 so according to theorem its diagonalisable but given is not diagonalizable so false.
b)its should be true because two different eigen values is 2 and 1.
c)false because eigen value repeated i.e 1,1 so false .