An electrical generator is switched on at time zero. The graph shows the total electrical energy generated in the first $5\ \text{s}$. What is the greatest electrical power generated at any instant during these first $5\ \text{s}$?
- A$10\ \text{W}$
- B$13\ \text{W}$
- C$30\ \text{W}$
- D$50\ \text{W}$