Answer:
The correct option is B)
Step-by-step explanation:
Consider the provided graph:
The general formula for equation of exponential decay is:
where 
The graph of exponential decay
where
as shown in figure 1:
From the figure 1, it is clear that <em>a </em>represents the <em>y</em> intercept and the coordinates are (0,<em>a</em>).
Now, consider the provided Graph:
The <em>y</em> intercept is (0,3)
Therefore, the value of <em>a</em> must be 3.
Now, consider the provided options, only option B) has the value of <em>a </em>= 3.
Therefore, the correct option is: B)
.