Answer: C . The author explains how through parent experiences, standards based grading made information unclear.
Explanation: Based off of the text it seems like the author is explaining through parent experiences how the standard based grading made information unclear. In paragraphs 1 the author starts to go into this by stating, "The report cards in Maryland's biggest school system left parents puzzled. They showed a wide range of elementary school subjects, but the same grade popped up again and again, the perplexing letter 'P' for proficient."(Paragraph 1) Then in paragraph 3 and 4 she explains what she means by this with parent experiences with the confusing report cards, "One mother from Montgomery county counted 80 of them on a fourth-quarter report card with a total of 84 grades. A father said that his children stopped paying attention to the grading reports all together, so unvaried was the marks that filled them"(Paragraph 3) and, "The all-inclusive P," said Cynthia Simson, a Derwood parent and longtime PTA leader who advocated for change." (Paragraph 4).