Draw the following aldotetrose in the proper Fischer projection.

• A.
• B.
• C.
• D.

Answer: (A)

Verified step by step guidance

1. Identify the structure of the aldotetrose from the first image. It is a four-carbon sugar with an aldehyde group at the top and hydroxyl groups on the second and third carbons.
2. Recognize that the Fischer projection is a two-dimensional representation of a molecule where the carbon chain is vertical, and horizontal lines represent bonds coming out of the plane towards the viewer.
3. Determine the configuration of the chiral centers in the given structure. The first chiral center (C2) has the hydroxyl group on the right, and the second chiral center (C3) has the hydroxyl group on the left.
4. Match the configuration of the chiral centers to one of the Fischer projections provided in the images. The correct Fischer projection will have the same arrangement of hydroxyl groups as the original structure.
5. Select the Fischer projection that corresponds to the structure with the hydroxyl group on the right at C2 and on the left at C3, which matches the original aldotetrose structure.