(image attached) what type of model is shown?
A) a structural formula
B) a chemical formula
C) a space-filling model
D) a ball-and-stick model

Option (A).

Explanation:

A). Structural formula

    Structural formula of a chemical compound represents a graphic structure of a molecule.

B). Chemical formula

    Chemical formula shows the chemical proportions of the atoms which constitute a molecule of the compound.

C). Space filling model

    Space filling model is a 3-D molecular model in which atoms are represented by the spheres whose radii are proportional to the radii of the atoms and distances between the atoms are proportional to the distances between the atomic nuclei.

D). A ball and stick model

    This model shows the 3-D positions of the atoms and the bonds between them.

    In this model atoms are represented by the spheres and bonds connected by the sticks.

Therefore, model shown is STRUCTURAL FORMULA.

Option (A) is the answer.