 Hello and welcome to the session. Let us discuss the following problem today. If delta is equal to determinant with elements a11, a12, a13, a21, a22, a23, a31, a32, a33 and aij is cofactors of aij then value of delta is given by a, a11, a31, a12, a32, a13, a33, b, a11, a11, a12, a21, a21, a13, a31, c, a21, a11, a22, a12, a23, a13, d, a11, a11, a21, a21, a31, a31, a31. We are small a denotes the element and capital a denotes the cofactor. Now let us write the situation. We know that delta is equal to sum of the product of elements of any row or column with their corresponding factors. Now we can see in our a option it does not contain all the elements from a single row or column similarly in b, c and d. Now our delta for the given determinant will be a11, a11 plus a21, a21 plus a31, a31. We are small a11, a21 and a31 are elements of the determinant and a11, a21 and a31 are cofactors of the determinant. Therefore, the required answer is option D. I hope you understood this session. Bye and have a nice day.