Answer: second option.
Explanation:
By definition, you know that:
![b^0=1](https://img.qammunity.org/2020/formulas/mathematics/high-school/w5cscie94c6ng67jfa050c4z4thm1a3ljg.png)
You can see in the graph that the interception with the y-axis is at -1.
Therefore, in that point: x=0 and y=-2
Substitute into the function and solve for a:
![-1=a(b)^0\\-1=a(1)\\a=-1](https://img.qammunity.org/2020/formulas/mathematics/high-school/zoi692msdb63daxr7h6xdin9jn9idoiefe.png)
Now, choose any point of the function and substitute this point and the value of a into the function and solve for b. Then you obtain:
Point (2,-4)
![-4=-1(b)^2\\(-4)/(-1)=b^2\\b=√(4)\\b=2](https://img.qammunity.org/2020/formulas/mathematics/high-school/ncmk9hs2f3dq50j0v9ic6u83jzvf9cnjgx.png)