The correct answer is A. A solution contains copper ions
Explanation:
Qualitative data always focuses on qualities, properties or characteristics, which is the opposite of quantitative data that focuses on numbers or statistics. According to this, the only one from the options that would be an example of qualitative data is "A solution contains copper ions" because this describes the solution through properties, qualities or characteristics, instead of numbers as it occurs in "A plant has five flowers" or "A solar system has nine planets".
