Four friends Abhay, Bina, Chhaya and Devesh were asked to simplify \(4 \mathrm{AB}+3(\mathrm{AB}+\mathrm{BA})-4 \mathrm{…

Four friends Abhay, Bina, Chhaya and Devesh were asked to simplify \(4 \mathrm{AB}+3(\mathrm{AB}+\mathrm{BA})-4 \mathrm{BA}\), where A and B are both matrices of order \(2 \times 2\). It is known that \(A \neq B \neq I\) and \(A^{-1} \neq B\).
Their answers are given as :
Abhay :\(6 \mathrm{AB}\)
Bina : \(7 \mathrm{AB}-\mathrm{BA}\)
Chhaya: \(8 \mathrm{AB}\)
Devesh : \(7 \mathrm{BA}-\mathrm{AB}\)
Who answered it correctly ?