Of the students at Creekview Middle School, \( 30 \% \) are in 6 th grade, \( 30 \% \) are in 7 th grade, and \( 40 \% \) are in 8 th grade. What is the estimated probability that at least one of the next three students entering the school will be a 7th grader?
Here are the results of a simulation using a random number generator.
- Let \( 1,2,3=6 \) th grader
- Let \( 4,5,6=7 \) th grader
- Let \( 7,8,9,0=8 \) th grader
\begin{tabular}{|c|l|l|l|l|l|l|l|l|l|l|}
\hline Group number & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 \\
\hline \begin{tabular}{c}
Random \\
digits
\end{tabular} & 602 & 433 & 791 & 398 & 041 & 209 & 467 & 570 & 221 & 407 \\
\hline
\end{tabular}
Which of the 10 groups show at least one 7 th grader?
A. \( 3,7,8,10 \)
B. \( 1,2,5,7,8,10 \)
C. \( 3,4,6,9 \)
D. \( 1,2,3,4,5,6,9 \)