Does a solution have to be a liquid mixture? Explain why or
why not.

No

Solutions can be solids dissolved in liquids. Solutions can also be gases dissolved in liquids, I.E carbonated water. You likely won't discover individuals making solid arrangements. They as a rule start off as solid/gas/fluid arrangements and afterward solidify at room temperature. alloys with a wide range of metals are genuine instances of solid arrangements at room temperature.

Explanation:

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

the answer is definitely c.