To determine which graph represents a proportional relationship, we need to look for a line that passes through the origin (0, 0). A proportional relationship has the form \(y = kx\), where \(k\) is a constant. This means that when \(x = 0\), \(y\) must also be \(0\).
Given your options:
- A line crosses the y-axis at (0, 2) — not proportional (does not pass through origin).
- A line crosses the y-axis at (0, 2) — not proportional (same as option 1).
- A curved line curves at (0, 0) — could represent a relationship but not necessarily proportional unless it's a straight line through the origin.
- A line crosses the y-axis at (0, 0) — proportional (passes through the origin).
Thus, the correct option that represents a proportional relationship is option 4.