The equation AgNO$_3$(aq) + NaCl(aq) $\longrightarrow$ AgCl$\downarrow$ + NaNO$_3$(aq) uses a downward arrow for AgCl. What does this indicate?

1. A downward arrow $\downarrow$ replaces the solid state symbol (s) when the product is an insoluble solid. 2. Such an insoluble solid that separates out is called a precipitate. 3. A gaseous product would carry an upward arrow $\uparrow$, so 'escapes as a gas' is wrong. 4. Aqueous state is shown by (aq) and heating by $\Delta$, so the aqueous and heating options are wrong. _Source: Balbharati (Maharashtra Board) Class 10 Science & Technology, Ch 3 "Chemical Reactions and Equations", p.42_