Motion — practice question

The diagram presents a velocity-time graph for an object that is accelerating. What is the object's acceleration?

• A$0.40\,\text{m s}^{-2}$
• B$2.5\,\text{m s}^{-2}$
• C$3.0\,\text{m s}^{-2}$
• D$100\,\text{m s}^{-2}$