Please explain questions 38,3940,41,42,43,44 and provide correct options also

1.38. Let A e an m * n matris. A matris of onder n N m is said to be a generalized inverse (or g-inverse) ofA if ) ABA B (ii) AB = O (i)A is singular tt 1, As ton (H)1A is fos sitıgulat bt i, A is (ii) both 1, - A anud 1 A at sihgul singulat (i) BAH a A (iv) ABA A singular 1.39. LetA be an m Xnmatrix. Theng-inverse (iv) both - A and A ar c of A is singular. (ii) finitely many (iv) none of these (i) unique ). A square tmatrix is a diagonal matii and only it it 1s 0 upper triangular (i) lower triangular (ii) infinitely many |40. LetA be an m xn matrix. Then g-inverse of A is unique if (i) m=n (ii) m