The correct option is C (−3√11,−1√11,−1√11)
The direction cosines of a line passing through the points P (x1,y1,z1) and
Q (x2,y2,z2) are
x2−x1PQ, y2−y1PQ, z2−z1PQ orx1−x2PQ, y1−y2PQ, z1−z2PQHere PQ=√(x1−x2)2+(y1−y2)2+(z1−z2)2=√(−1−2)2+(2−3)2+(4−5)2=√9+1+1=√11
Hence D.C.'s are
(−3√11,−1√11,−1√11) or (3√11,1√11,1√11)