
Option C is Correct.
More about Tangent
Slope = 0 → Line is parallel to x-axis
Slope > 0 → Line goes upward (left to right)
Slope < 0 → Line goes downward (left to right)
Slope = +1 → Line rises at 45°
Slope = −1 → Line falls at 45°
So in general:
If slope ≠ 0, the tangent is slanted, not horizontal.