To find the equation of the line, we need two key elements:

1. Slope: From the graph, we can count the rise over run. The line appears to descend from left to right, which means the slope is negative. From one point to another, it goes down by 2 units for every 4 units it moves to the right. This gives a slope of $\frac{-2}{4} = -\frac{1}{2}$.

2. Y-intercept: The point where the line crosses the y-axis is at $y = 2$.

So, the equation of the line in slope-intercept form $y = mx + b$ is:

$y = -\frac{1}{2}x + 2$

The correct answer is: $y = -\frac{1}{2}x + 2$ (which is the last option).

Would you like more details or have any questions?

Here are some related questions:

1. How do you calculate the slope if the graph doesn't show exact points?
2. What is the significance of the y-intercept in a linear equation?
3. Can the slope of a line be positive if it goes down from left to right?
4. How would the equation change if the line were parallel to this one?
5. What happens to the equation if the y-intercept is negative?

Tip: When finding the slope from a graph, always ensure that both points are accurately identified to avoid errors in the rise-over-run calculation.