Answer:
The correct answer is the option: d. mixture.
Step-by-step explanation:
Hello! Let's solve this!
Pure gold is a mixture, since it is mixed with some other metal to increase its characteristics.
Pure gold or fine gold is 24-karat gold.
A mixture is the union of one or more elements, but they are not chemically linked.
We conclude that the correct answer is the option: d. mixture.