Answer:
A.
Step-by-step explanation:
"Marie Curie" by Barrett Smith is an article that describes the life of Marie Curie and her achievements.
In the article, Smith remarks on how Marie's focus was shifted during World War I in providing aid to the soldiers who were injured in the war. When she saw that there was a shortage of the X-ray machine, so with the help of her daughter she invented portable X-ray machines which can be brought to the field to aid the soldiers.
Therefore, the correct answer is option A.