In the reaction[phenol + CHCl_3 + NaOH → sodium salicylaldehyde (o-O^-Na^+ C_6H_4 CHO), shown as a structure]the electrophile involved is
In the reaction
[phenol + CHCl\(_3\) + NaOH \(\rightarrow\) sodium salicylaldehyde (o-O\(^-\)Na\(^+\) C\(_6\)H\(_4\) CHO), shown as a structure]
the electrophile involved is

1. dichloromethyl cation (\(\overset{\oplus}{C}\)HCl\(_2\))
2. dichloromethyl anion (\(\overset{\ominus}{C}\)HCl\(_2\))
3. formyl cation (\(\overset{\oplus}{C}\)HO)
4. dichlorocarbene (:CCl\(_2\))