To avoid error you should read the scale of an aneroid barometer with your eye placed __________.

Correct Answer: Option D — directly in front of the pointer

Parallax error occurs when the observer's line of sight is not perpendicular to the instrument scale. To ensure an accurate reading of the pointer against the graduated scale of an aneroid barometer, the eye must be positioned directly in front of the pointer to eliminate visual distortion of the measurement.