Scientists William D. Phillips, Claude Cohen-Tannoudji, and Steven Chu won the Nobel Prize in Physics in 1997 for the “development of methods to cool and trap atoms with laser light,” which became the foundation for the study of atomic physics. Their findings have led to the development of more accurate atomic clocks, and the improvement of new devices that can solve problems faster than modern computers is underway.Choice D is the best answer. The convention being tested is the use of possessive determiners. The plural possessive determiner “their” agrees in number with the plural noun phrase “scientists William D. Phillips, Claude Cohen-Tannoudji, and Steven Chu,” thus indicating that the findings are those of these scientists.
Choice A: “It’s” is the contraction for “it is” or “it has,” which is not a possessive determiner.
Choice B: “They’re” is the contraction for “they are,” which is not a possessive determiner.
Choice C: The singular possessive determiner “its” does not agree in number with the plural phrase “scientists William D. Phillips, Claude Cohen-Tannoudji, and Steven Chu.”
✨ Expert's Tip ✨
A possessive determiner is a pronoun that is used to express belongingness. It shows who owns or possesses something.
