To find the probability that a randomly selected student is in 9th grade and chose pizza, we will use the information in the table.
- The number of 9th graders who chose pizza is 30.
- The total number of students surveyed is 450.
The probability can be calculated using the formula:
\[ P(\text{9th grade and chose pizza}) = \frac{\text{Number of 9th graders who chose pizza}}{\text{Total number of students}} = \frac{30}{450} \]
Calculating this gives:
\[ P(\text{9th grade and chose pizza}) = \frac{30}{450} = \frac{1}{15} \approx 0.0667 \text{ or } 6.67% \]
Therefore, rounding to the nearest whole percentage, the correct answer is:
7%
So the answer is 7%.