Final answer:
A. Linear acceleration. The receptors in the otolithic organs respond to linear movement of the head. This is called Linear acceleration.
Step-by-step explanation:
The receptors in the otolithic organs respond to linear movement of the head. This is called Linear acceleration. The otolithic organs, which include the utricle and saccule, are responsible for detecting changes in linear acceleration, such as when gravity acts on the tilting head or if the head starts moving in a straight line.