If \(\vec a,\; \vec b\) and \(\vec c\) are the position vectors of the vertices A, B, C of a triangle ABC, then the area of the triangle ABC is

• A. \(\frac 1 2 |\vec a \times \vec b + \vec b \times \vec c + \vec c \times \vec a|\)
• B. \(|\vec a \times \vec b|\)
• C. \(\frac 1 2 |\vec a \times \vec b - \vec b \times \vec c \times -\vec c \times \vec a|\)
• D. \(|\vec a \times (\vec b \times \vec c)|\)