\(ƒ(x) = x^4 – 4x + 1 = 0\)
\(ƒ′(x) = 4x^3 – 4\)
= \(4(x – 1) (x^2 + 1 + x)\)

Hence, the correct option is (B): \(2\)
Which one of the following graphs accurately represents the plot of partial pressure of CS₂ vs its mole fraction in a mixture of acetone and CS₂ at constant temperature?
