A is parallel to B then A.B =

Explanation

The dot product of two vectors A and B is given by the formula A·B = |A| |B| cos(θ), where θ is the angle between the vectors. For parallel vectors, θ = 0°. The cosine of 0° is 1, so the dot product simplifies to |A| |B|, or AB.Option A is incorrect because a dot product of zero indicates perpendicular vectors, not parallel ones. Option C is incorrect as it suggests a negative product which would apply if the vectors were anti-parallel. Option D is not a valid mathematical expression for a dot product. Option E is incorrect as the dot product for parallel vectors is not 'none'.