A, B, C and D are standing on the four corners of a square field as shown in the figure. From the positions shown in the figure, A walks to North position and B walks to the East position while C decides to walk two sides in anticlockwise direction. B walks to North and then changes his mind to take the previous position. Identify the choice with correct positions.
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Move each person one edge at a time along the square, starting from A, then B, then C two sides anticlockwise, and remember D never moves.
Step 1: Understanding the Question. The figure shows B at the top left corner, C at the top right corner, A at the bottom left corner, and D at the bottom right corner, with north pointing upward. So the corners are, A at south west, B at north west, C at north east, D at south east. We need to track where each person ends up after their moves and check which option correctly describes the final layout.
Step 2: Key Approach. Each person's move is described relative to their own current position along the edges of the square, so we move one person at a time along the boundary of the square and note their new corner.
Step 3: Detailed Explanation. A starts at south west and walks to the North position, meaning A moves north along its own side of the square, from south west up to north west. So A ends up at north west, the corner B started at. B starts at north west and walks to the East position, meaning B moves east along the top side of the square, from north west to north east. So B ends up at north east, the corner C started at. C starts at north east and walks two sides in the anticlockwise direction. Walking around the square anticlockwise from north east, the first side takes C to north west, and the second side takes C onward to south west. So C ends up at south west, the corner A started at. D is never mentioned as moving at any point, so D stays at south east the whole time. The extra sentence about B walking to North and then changing his mind to take the previous position describes B considering a further move north from north east, then abandoning it and returning to the position B was already at just before that, which is the north east corner reached by the earlier East walk. So this sentence confirms B's final position stays at north east, it does not change the result found above.
Step 4: Final Answer. Final positions: A at north west, B at north east, C at south west, D at south east (unchanged). Checking the options: A and B are at different corners, so option (1) is wrong. C and D are at different corners, so option (2) is wrong. D is at its original corner but B is not, since B moved from north west to north east, so option (3) is wrong. B is at north east and C is at south west, and these two corners are diagonally opposite each other on the square, so option (4), B and C are diagonally opposite positions, is correct.
