1. which of the following structures in the diagram below enables the observer to identify that it is a plant cell? a. 1 and 3 b. 1 and 2 c. 2 and 3 d. 2 and 4

You did not provide a drawing but if you the distinguishing features of a plant cell is the presence of chloroplasts and you will notice also that the vacuole is rather big compared to an animal cell. You will also see that a plant cell has a cell wall instead of a cell membrane. It is more rigid than the animal cell membrane.

Cell wall, big vacuole and chloroplasts.  That would indicate that the observer is looking at a plant cell.