Fixed

You can either draw or visualize.

The point \((4a,b)\) will be at the same height \(b\) as point \((a,b)\), and form the base of the triangle, whereas the point \((2a,2b)\) will be the apex of the triangle.

\(base = 4a-a = 3a\) (subtracting the x-coordinate of the points \((a,b)\) and \((4a,b)\))

\(height = 2b-b \) (subtracting the y-coordinate of \((2a,2b)\) and \((a,b)\))

\(\text{ Area of Triangle } = \dfrac{1}{2} \times base \times height = \dfrac{1}{2} \times 3a \times b = \dfrac{3ab}{2}\)

The answer is Choice C