To find the area of Triangle C using the standard formula for the area of a triangle, you can use the formula:
\[ \text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \]
If Triangle C is positioned in a way that the base is along one of the sides of the grid and the height is perpendicular to the base, you should identify the length of the base and the height.
From the description of the grid, if Triangle C has a base of 9 units and a height of 5 units, you would calculate the area as follows:
\[ \text{Area} = \frac{1}{2} \times 9 \times 5 = \frac{1}{2} \times 45 = 22.5 \text{ square units} \]
However, if the dimensions or placements are different and result in an area of 10.5 square units, that would suggest a smaller base and height than the maximum grid dimensions.
Since you provided possible answers, and assuming that the area calculation aligned with the options given highlights an area of 10.5 square units, the answer would be:
10.5 square units.
If you can provide the dimensions or any other details of Triangle C, I can verify the calculation accordingly!