Nine people sit in a 3×3 square, each corner and center occupied. A is adjacent to B (not diagonally). C is at a corner adjacent to D. E is opposite F. Who is in center if G is at a corner?
Correct: B
Grid arrangements require considering adjacency rules. A-B relation fixes corners, C-D constraints reduce corner possibilities. Opposite pairs E-F narrow candidates for central position when G's corner placement is factored in.