Step 1: Equation of tangents.
Use the parametric equations to find the derivatives of the curve to obtain the slopes of the tangents at the points where the curve intersects the x-axis. Then calculate the angle between the tangents.
Step 2: Conclusion.
Thus, the correct answer is option (C).
Final Answer:
\[
\boxed{\text{(C) } \pm \tan^{-1} \left( \frac{10}{49} \right)}
\]