The constraints are:
\[
x \geq 0, \quad y \geq 0, \quad x + y \geq 4.
\]
1. Constraint Interpretation:
* \( x \geq 0 \): Region is to the right of the \( y \)-axis.
* \( y \geq 0 \): Region is above the \( x \)-axis.
* \( x + y \geq 4 \): Region is on or above the line \( x + y = 4 \).
2. Feasible Region:
This region is the intersection of the constraints within the first quadrant. The line \( x + y = 4 \) intersects the axes at \( (4, 0) \) and \( (0, 4) \). As \( x \geq 0 \) and \( y \geq 0 \), these points define the boundary. The feasible region is unbounded, with corner points at \( (4, 0) \) and \( (0, 4) \).
3. Corner Point Count:
There are exactly two corner points in the feasible region.
Therefore, the answer is (C) 2.