LED glows even when a - electric current passes through it.

Explanation

To solve the question "LED glows even when a - electric current passes through it," we need to identify the type of electric current that allows an LED (Light Emitting Diode) to function effectively.

### Step-by-Step Solution:

1. **Understanding LED**:
- An LED, or Light Emitting Diode, is a semiconductor device that emits light when an electric current flows through it.

2. **Current Requirement**:
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