The position vectors of three consecutive vertices of a parallelogram are i + j + k, i + 3j + 5k and 7i + 9j + 11k the position vector of the fourth vertex is

The position vectors of three consecutive vertices of a parallelogram

1.	The position vectors of three consecutive vertices of a parallelogram are i + j + k, i + 3j + 5k and 7i + 9j + 11k the position vector of the fourth vertex is
A.	6(i - j + k)
B.	7(i + j + k)
C.	2j - 4k
D.	6i + 8j + 10k
Answer» C. 2j - 4k