Sarah's younger siblings are always bothering her when she does her homework, and she begins to wonder whether other students have the same trouble. She surveys 25 of her fellow juniors and records the number of siblings and the homework grades for each of them. According to the scatterplot Sarah produced from this data, which conclusion is MOST justified? [Note: x is the number of siblings, y is the homework grade.] A) Siblings have a mixed effect on homework performance. B) Siblings have a positive effect on homework performance. C) Siblings have a negative effect on homework performance. D) Siblings have little or no effect on homework performance.