Critical Reasoning

A broken shard of glass found in the laboratory of the famed physicist Alhazenhas a polished surface that separates out the green and blue spectrums of white light, a key characteristic of a dispersive prism, which separates white light into all its constituent spectral components. Scientific historians, based on this finding, are revising their histories in order to give Alhazen, the "father of modern optics," credit for the discovery of the dispersive prism, which was thought to have been discovered many years later.
Which of the following, if true, most strongly supports the historians' decision to revise the history of optics?

1.Dispersive prisms were the only type of prism that was theorized about in the scientific era in which Alhazenlived.

2.The piece of glass from which the shard broke, if unbroken, would have been just large enough to separate out the entire spectrum of white light into its spectral components.

3.The piece of glass was a combination of flint glass, which was known to have been used by Alhazento craft lenses in his laboratory, and crown glass, another popular type of glass throughout history.

4.Dispersive prisms are the simplest and most common objects that are able to divide white light into its constituent spectral components.

5.Several glass objects that are known to have some properties of a dispersive prism have been found to be older than the glass piece in Alhazen'slaboratory.

bharti.2010 wrote:A broken shard of glass found in the laboratory of the famed physicist Alhazenhas a polished surface that separates out the green and blue spectrums of white light, a key characteristic of a dispersive prism, which separates white light into all its constituent spectral components. Scientific historians, based on this finding, are revising their histories in order to give Alhazen, the "father of modern optics," credit for the discovery of the dispersive prism, which was thought to have been discovered many years later.
Which of the following, if true, most strongly supports the historians' decision to revise the history of optics?

1.Dispersive prisms were the only type of prism that was theorized about in the scientific era in which Alhazenlived.

2.The piece of glass from which the shard broke, if unbroken, would have been just large enough to separate out the entire spectrum of white light into its spectral components.

3.The piece of glass was a combination of flint glass, which was known to have been used by Alhazento craft lenses in his laboratory, and crown glass, another popular type of glass throughout history.

4.Dispersive prisms are the simplest and most common objects that are able to divide white light into its constituent spectral components.

5.Several glass objects that are known to have some properties of a dispersive prism have been found to be older than the glass piece in Alhazen'slaboratory.

The argument is that the shard of glass made the historians attribute the discovery of the prism to the physicist. We have to see what choice bolsters this claim:

1. They were theorized but not clear they were discovered.

2. The unbroken piece would separate out the entire spectrum which is what a prism would do. Hence, strong choice.

3. Could craft lenses does not relate to prisms.

4. Ok so what? How does it support the argument?

5. Weakens the argument by positing that most probably the prism was discovered earlier than the physicist's time.

Hence only choice 2 stands.

Conclusion: Historians give A credit for prism.

Evidence: Glass found that has characteristic of prism.

Assumption: Glass not there by accident; glass definitely means A "discovered" prism.

Question: What STRENGTHENS?

Prediction: Anything that links this glass to the prism, removes coincidence.

A - Other prisms out of scope.
B - This connects the glass to the prism.
C - The type of glass is irrelevant.
D - This is just a fact about the prism.
E - This would weaken, since it makes the glass/prism link less strong.

My choice is B as well.

Thanks MJ and Vivian.