The dice has 6 faces numbered 1 to 6.
The probability of landing any number is 1/6.
The expected value is the sum of products of the probability and the winnings/losings.
So the expected value in this case is given by:
[tex]\begin{gathered} E(X)=\frac{1}{6}\times20+\frac{1}{6}\times40+\frac{1}{6}\times(-30)+\frac{1}{6}\times0+\frac{1}{6}\times0+\frac{1}{6}\times0 \\ E(X)=\frac{20+40-30}{6} \\ E(X)=5 \end{gathered}[/tex]
So the player can expect to win $5 per game in the long run.
Option C is correct.