Answer: A, B, D
The compound is 2,3,4,4-tetramethylhexane (C10H22). The six-carbon chain carries four methyl groups; numbering from the end nearer the branches gives {2,3,4,4}, which beats {3,3,4,5} at the first point of difference (2 < 3). The carbon with two methyls and the ethyl-bearing neighbour is a quaternary carbon.