Each compound is shaken at room temperature with aqueous ethanolic $\mathrm{AgNO}{}_3$. Which give a white precipitate of AgCl within seconds?

Immediate precipitation requires easy ionisation to a stable carbocation. The tertiary tert-butyl cation and the very stable trityl cation form readily. Chlorobenzene and chloroethene have C-Cl bonds with double-bond character and do not ionise under these conditions.