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Four students \(A\), \(B\), \(C\) and \(D\) looked through pipes of different shapes to see a candle flame as shown in figure.
 
YCIND_220922_4494_figure_11_4a.png
V-shaped pipe
 
YCIND_220922_4494_figure_11_4b.png
Zig-zag pipe
 
YCIND_220922_4494_figure_11_4c.png
Curvy pipe
 
YCIND_220922_4494_figure_11_4d.png
Straight pipe
 
Who will be able to see the candle flame clearly?