The inductive effects of the group `-CH_(3),-COO^(-),-Br,-NH_(3)^(+)` respectively are

Options

A. `+I,-I,+I,+I`
B. `-I,+I,-I,+I`
C. `-I,-I,+I,+I`
D. `+I,+I,-I,-I`

Explanation

To determine the inductive effects of the groups -CH₃, -COO⁻, -Br, and -NH₃⁺, we need to analyze each group based on its ability to either donate or withdraw electron density through the sigma bonds.

### Step-by-Step Solution:

1. **Identify the Groups**: We have four groups to analyze: -CH₃, -COO⁻, -Br, and -NH₃⁺.

2. **Analyze -CH₃ (Methyl Group)**:
- The -CH₃ group is an alkyl group. Alkyl groups are known to donate electron density through the inductive effect.
- Therefore, the inductive effect of -CH₃ is **+I (positive inductive effect)**.

3. **Analyze -COO⁻ (Carboxylate Ion)**:
- The -COO⁻ group is a carboxylate ion. The oxygen atom in this group can participate in resonance, which stabilizes the negative charge.
- However, the carbon atom in the -COO⁻ group can still donate some electron density through the sigma bond, leading to a **+I effect**.
- Thus, the inductive effect of -COO⁻ is also **+I**.

4. **Analyze -Br (Bromine)**:
- Bromine is a halogen and is known to withdraw electron density due to its electronegativity.
- Therefore, the inductive effect of -Br is **-I (negative inductive effect)**.

5. **Analyze -NH₃⁺ (Ammonium Ion)**:
- The -NH₃⁺ group has a positive charge on nitrogen, which indicates that it is electron-deficient.
- As a result, this group will withdraw electron density from the surrounding atoms.
- Therefore, the inductive effect of -NH₃⁺ is also **-I**.

### Summary of Inductive Effects:
- -CH₃: +I
- -COO⁻: +I
- -Br: -I
- -NH₃⁺: -I

### Final Answer:
- The inductive effects of the groups are:
- -CH₃: +I
- -COO⁻: +I
- -Br: -I
- -NH₃⁺: -I