Which of the following pairs is expected to exhibit H-bonding
(a) `CH_(3)CH_(2)OH` and `CH_(3)OCH_(3)`
(b) `CH_(3)NH_(2)` and `CH_(3)SH`
(c ) `CH_(3)OH` and `(CH_(3))_(3)N` .

Explanation

To determine which of the given pairs is expected to exhibit hydrogen bonding, we need to analyze each pair based on the presence of hydrogen atoms bonded to highly electronegative atoms (such as nitrogen, oxygen, or fluorine) and the size of these atoms.

### Step-by-Step Solution:

1. **Understanding Hydrogen Bonding**:
- Hydrogen bonding occurs when a hydrogen atom is covalently bonded to a highly electronegative atom (N, O, or F). The electronegative atom attracts the shared electrons, creating a dipole moment where the hydrogen atom becomes slightly positive and the electronegative atom becomes slightly negative.

2. **Analyzing the First Pair: `CH3CH2OH` and `CH3OCH3`**:
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