Arrange the following alkenes towards order of increasing reactivity in cationic polymerization:
`H_(2)C=CHCH_(3), CICH=CH_(2), H_(2)C=CHC_(6)H_(5)`,
`H_(2)C=CHCOOCH_(3)`

Explanation

To determine the order of increasing reactivity of the given alkenes in cationic polymerization, we need to analyze the stability of the carbocations that would form during the polymerization process. The more stable the carbocation, the more reactive the alkene will be in cationic polymerization.

### Step-by-Step Solution:

1. **Identify the Alkenes**:
The alkenes provided are:
- A: \( H_2C=CHCH_3 \)
- B: \( ClCH=CH_2 \)
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