Answer: Option (a) is the correct answer.
Step-by-step explanation:
A compound is a substance that contains two or more different atoms which are combined chemically in a similar composition.
For example, NaCl is also known as table salt and it is a compound.
Also, sucrose and baking soda are both compounds as the contain similar composition of the atoms present in it.
Whereas salad dressing is not a compound as there are different composition of the atoms present in it.
Thus, we can conclude that salad dressing is the item that is not a compound.