If `theta` is the angle between any two vectors ` veca` and ` vec b`, then `| veca . vecb |=| veca xx vecb|` when `theta` is equal to(A) 0 (B) `pi/4` (C) `pi/2` (D) `pi`

Explanation

To solve the problem, we need to find the angle \( \theta \) between two vectors \( \vec{a} \) and \( \vec{b} \) such that the magnitude of their dot product is equal to the magnitude of their cross product.

### Step-by-step Solution:

1. **Write the expressions for dot product and cross product:**
- The dot product of two vectors is given by:
\[
|\vec{a} \cdot \vec{b}| = |\vec{a}| |\vec{b}| \cos \theta
...