How do the two main classifications of matter differ

Iknow the answer is a but i don't know why

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

Draw the lewis dot structure for each of the following polyatomic ions