To interpret the constant term, evaluate the model when $c=0$.

After you find $\hat{s}$ when $c=0$, describe what that means using the context of cameras and sightings.

In Desmos, enter $s = 3 + 1.6c$.

Use a table (or click the graph) to see the value of $s$ when $c=0$.

The value at $c=0$ is the predicted number of deer sightings when 0 cameras are deployed, which matches the correct choice.

In $\hat{s} = 3 + 1.6c$, the constant term is $3$. This is the y-intercept of the line of best fit.

The y-intercept gives the predicted value of $\hat{s}$ when $c=0$.

So the model predicts $3$ deer sightings in a week when 0 cameras are deployed.

Therefore, the correct choice is: The predicted number of deer sightings in a week when 0 cameras are deployed is 3.