All naturally occurring amino acids possess ...................... configuration.

Explanation

To answer the question "All naturally occurring amino acids possess ...................... configuration," we can follow these steps:

### Step 1: Understand the Configuration of Amino Acids
Amino acids can exist in different configurations based on the arrangement of their atoms around the central carbon atom (the alpha carbon). The two main configurations are L (levo) and D (dextro).

**Hint:** Recall that the configuration of amino acids is determined by the position of the amino group (NH2) and the carboxyl group (COOH) relative to the alpha carbon.

### Step 2: Identify the Common Configuration
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