Junior Mathematical Olympiad, September 2019

In a class, $30$ students did a test. Every student got a grade that was an integer from $1$ to $10$. The grade $8$ was given more often than any of the other grades. What is the smallest possible average grade of the students? A) $3\frac{8}{15}$ B) $3\frac{2}{3}$ C) $3\frac{5}{6}$ D) $4\frac{11}{30}$ E) $4\frac{8}{15}$