b
As \(CHCl _3\) has \(Cl\) more electronegative than \(H\) so it has not regular geometry Regular geometry of \(CH _4\) is attributed to zero dipole moment \((\mu=0)\) and absence of lone pair on the carbon atom.
\(SF _4\) has lone pair on \(S\) so it will increase bond angle due to repulsion hence \(CHCl _3\) and \(SF _4\) has not regular geometry.