Order of decreasing basic strengths of halides is :

Options

A. `F^(-) gt Cl^(-) gt I^(-) gt Br^(-)`
B. `F^(-) gt Cl^(-) gt Br^(-) gt I^(-) `
C. `I^(-) gt Br^(-) gt CI^(-) gt F^(-) `
D. `I^(-) gt Cl^(-) gt Br^(-) gt F^(-) `

Explanation

To determine the order of decreasing basic strengths of halides, we will analyze the acidic strengths of their corresponding acids first, and then infer the basic strengths of the halides from that information.

### Step-by-Step Solution:

1. **Identify the Halides and Their Corresponding Acids**:
- The halides we are considering are: I⁻, Br⁻, Cl⁻, and F⁻.
- Their corresponding acids are: HI, HBr, HCl, and HF.

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