( A ) Base $\to$ Weak , Acid $\to$ Strong , End point $\to$ Colourless to pink
( B ) Base $\to$ Strong , Acid $\to$ Strong , End point $\to$ Pinkish red to yellow
( C ) Base $\to$ Strong , Acid $\to$ Strong , End point $\to$ Pink to colourless
( D ) Base $\to$ Weak , Acid $\to$ Strong , End point $\to$ Yellow to pinkish red