Final answer:
The kind of eye movement made when rapidly shifting gaze to the source of a loud noise is called a saccade. Saccades are rapid, ballistic eye movements that change the point of fixation to quickly direct attention to a new visual stimulus, such as the potential source of a sound. Option A is the correct answer.
Step-by-step explanation:
If you hear a loud noise and rapidly shift your eyes to point in the direction of where the noise came from, the kind of eye movement you are making is a saccade. Saccades are quick, ballistic eye movements that abruptly change the point of fixation.
They are used both to survey a visual scene and to follow moving visual stimuli. During this process, the eyes move together in the same direction, which is known as conjugate gaze.
Saccades are distinct from pursuit movements which involve the smooth tracking of moving objects, vergence movements which are the adjustment of the angle of convergence of the eyes to ensure focus on an object as it moves closer or farther away, and nystagmus which is an involuntary, rhythmic oscillation of the eyes.
When a loud noise captures your attention, the auditory cue prompts your visual system to quickly relocate the focus of your gaze onto the potential source of the sound, resulting in a saccadic movement.