What would you expect to be soluble in the nonpolar solvent carbon disulfide?

Non-polar solvents are those that are made from hydrocarbons. Carbon disulfide isn't completely non-polar, because it has sulfur in it. Sulfur is an atom (like oxygen) that can attract electrons away from other atoms. This is what makes things non-polar when one atom tends to pull the electrons away from the others within the same molecule. The strongest attractors (most electronegative are at the top-right of the periodic table). The weakest and most likely to give up electrons (most electropositive) are at the bottom left of the periodic table. When you have either of these extremes, you end up with a polar molecule. So this rules out the Cl4. Wait a minute. There is no such thing as Cl4. Chlorine comes in pairs (Cl2). Did you possible mean CCl4 (carbon tetrachloride)? If so, it would be the least polar on the list because it has carbon and no metal atoms, so it's an organic molecule. It would therefore be soluble or more accurately miscible in CS2 (they are both solvents).