Introduction:
The inductive effect is the effect of electron withdrawal or donation through the sigma bond of a molecule. It can be either positive or negative. In the case of amine molecules, the inductive effect is observed due to the presence of a lone pair of electrons on the nitrogen atom. In this question, we need to compare the inductive effect of N(CH3)3 and NH3.

N(CH3)3 has a higher negative inductive effect:
The inductive effect of a molecule is dependent on the electronegativity of the atoms attached to the central atom. Here, we need to compare the electronegativity of the methyl group (CH3) and the hydrogen atom (H) attached to the nitrogen atom in N(CH3)3 and NH3, respectively.

• The electronegativity of carbon is 2.55, while that of hydrogen is 2.20.


• The electronegativity difference between carbon and nitrogen is less than that between hydrogen and nitrogen.


• Thus, the electron density on the nitrogen atom in N(CH3)3 is reduced to a greater extent than in NH3 due to the presence of three methyl groups, which are electron-withdrawing groups.

Conclusion:
Therefore, N(CH3)3 shows a more negative inductive effect than NH3 due to the presence of three methyl groups, which are more electronegative than hydrogen and withdraw more electron density from the nitrogen atom.

N(CH3) HAS MORE NEGATIVE INDUCTIVE EFFECT BECAUSE CH3 HAS MORE POSITIVE INDUCTIVE EFFECT COMPARED TO H SO NITROGEN GETS MORE NO.OF ELECTRONS IN NCH3 COMPARED TO NH3