In the given case, Candice is incorrect. Hence, the correct answer is option 2.
As substance A is a pure substance because it is a compound. A compound is formed of two or more different elements and they are bonded together. On the other hand, substance B is a mixture, as it is made up of two elements that are not bonded together. Mixtures can be separated with the help of physical methods, while compounds cannot be separated with the help of physical methods.