Four students A, B, C, and D looked through pipes of different shapes to see a candle flame as shown in the figure. Who will be able to see the candle flame clearly?
The explanation for the correct answer
In the case of option D,
The explanation for the incorrect answer
In the case of option A,
The tube in option (a) is not straight. As a result, we won't be able to properly observe the candle flame.
In the case of option B,
The tube in the given option is curved. As a result, we won't be able to properly observe the candle flame.
In the case of option C,
the tube in option (c) is bent. As a result, we won't be able to properly observe the candle flame.
Hence, option D is the correct answer.