This problem involves deciphering a code language based on given examples.

Decoding Logic for 'mom' Code

We need to find the code for the word 'mom' using the provided coded phrases:

• 'desk round mom' is coded as 'md ei wx'
• 'mom wheat bell' is coded as 'um ac ei'

Step-by-Step Solution

1. Identify Common Words: Observe that the word 'mom' appears in both the original phrases: 'desk round mom' and 'mom wheat bell'.
2. Identify Common Codes: Compare the codes for both phrases: 'md ei wx' and 'um ac ei'. The common code word between these two is 'ei'.
3. Match Common Word to Common Code: Since 'mom' is the common word in the original phrases, its corresponding code must be the common code word found, which is 'ei'.

Final Code Determination

Therefore, in this specific code language:

• 'desk round mom' corresponds to {'md', 'ei', 'wx'}
• 'mom wheat bell' corresponds to {'um', 'ac', 'ei'}

The common word 'mom' maps to the common code 'ei'.