According to VSEPR theory, in which species do all the atoms lie in the same plane?

(p) ${\mathrm{CH}}_3^{+}$               (q) ${\mathrm{CH}}_3^{-}$

According to VSEPR theory:

• CH3⁺ (option p): This is a carbocation with 3 bonding pairs and no lone pairs on the carbon. Its geometry is planar trigonal (sp² hybridized), so all atoms (C and three H) lie in the same plane.
• CH3⁻ (option q): This is a methyl anion with 3 bonding pairs and 1 lone pair on carbon. Its geometry is pyramidal (sp³ hybridized), so all atoms do not lie in the same plane.