If the amount of red is reduced in red-violet, which way will the colour shift?

Correct answer: Toward violet

The governing concept is colour bias caused by changing component proportions. Red-violet is a mixture of red and violet. If the red component is reduced while the violet remains, violet contributes more strongly to the visual appearance. Thus option C, toward violet, is correct. Orange, green, and yellow are not the remaining component and would require adding or increasing other colour influences.