Answer 1

If `x = alpha`, is a zero of a polynomial then `x -alpha `is a factor of  `f(x)`

Since 3 is the zero of the polynomial , f(x) = x² − 5x + 4,

Therefore `x - 3`is a factor of  `f(x)`

Now, we divide`f(x) = x^2 - 5x + 4 ` by  `(x - 3)` we get

Therefore we should add 2 to the given polynomial

Hence, the correct choice is (b).