The question asks about the effect on the graph when the y-intercept of a function is changed to a smaller positive number.

In the equation of a linear function $y = mx + b$, where $m$ represents the slope and $b$ represents the y-intercept, changing the value of $b$ shifts the graph up or down. When the y-intercept $b$ is decreased (changed to a smaller positive number), the entire line shifts downward because the starting point on the y-axis is lower.

Therefore, the correct answer is: B. The line shifts down.

Would you like further details or have any questions?

Here are some related questions:

1. What happens to the graph if the y-intercept is changed to a negative number?
2. How does changing the slope $m$ affect the graph of the function?
3. What effect does increasing the y-intercept have on the graph of a line?
4. How do horizontal shifts affect the graph of a linear function?
5. Can a line have the same slope but different y-intercepts? If so, what does that mean graphically?

Tip: The y-intercept is the point where the graph crosses the y-axis (where $x = 0$). Adjusting it shifts the graph up or down without changing its slope.