When drawing a fischer projection of a sugar, the horizontal line represents groups that are
a. projecting out of the plane of the drawing toward you
b. both hydroxyl groups
c. both hydrogen atoms
d. projecting behind the plane of the drawing

The correct answer is a. projecting out of the plane of the drawing toward you.

Explanation:

Fisher's projection represents a way of showing tetrahedral carbon atoms with their substituent groups. . The vertical lines represent the groups that move away and the horizontal lines those that approach.