What can cause a skewing effect in MRI images?

A malfunctioning gradient coil or amplifier can indeed lead to a skewing effect in MRI images. The gradient coils are essential for encoding spatial information in the MRI data. When these coils are not functioning correctly, they may distort the magnetic field gradients, resulting in inaccurate spatial localization of signals. This malfunction can create artifacts in the images, which can manifest as skewing or warping of the displayed anatomy. Accurate gradient performance is crucial for maintaining the integrity of the imaging process, as even minor deviations can significantly affect the quality of the images produced.

The other options pertain to different aspects of MRI imaging. Using too high a frequency could affect signal-to-noise ratios but is not directly responsible for skewing. Inadequate slice selection influences the delineation of anatomies rather than causing skewing in the images. Lastly, insufficient image slice thickness relates to resolution and the ability to capture anatomical details but does not typically result in skewing effects. Therefore, the malfunctioning gradient coil or amplifier is the correct answer regarding the cause of skewing in MRI images.