Explanation
Correct answer: A.
Choice A is the best answer. The sentence emphasizes the order in which Alaska and Hawaii became US states, noting that Alaska became a US state several months before Hawaii did.
Why the other choices are wrong
Choice B
Choice B is incorrect. The sentence specifies when the 50-star US flag was unveiled; it doesn’t emphasize the order in which Alaska and Hawaii became US states.
Choice C
Choice C is incorrect. While the sentence indicates that the 49th and 50th states became US states in the same year, it doesn’t identify which state was the 49th and which was the 50th; as a result, it doesn’t emphasize the order in which Alaska and Hawaii became states.
Choice D
Choice D is incorrect. The sentence indicates that a new US flag was unveiled when Hawaii became a US state; it doesn’t emphasize the order in which Alaska and Hawaii became states.