All of the following are classified as acids except
a. vinegar.
b. soda pop.
c. orange juice.
d. a bar of soap.

All of the followings are classified as acids except (D.) A BAR OF SOAP. A bar of soap is a base since it has a strong alkaline content. The vinegar, soda pop, and orange juice is obviously an acid since this contains acetic acid and many more.

The component from the mentioned ones which isn't an acid would be a bar of soap - d.

Vinegar, soda pop, and orange juice are all acids because they have a certain content of acid while the bar of soap has a strong alkaline element to it. You could measure this with a normal pH measurement.