Final answer:
Double-checking claim accuracy is the action that prevents fraud in billing and coding, ensuring claims reflect the true services provided.
Step-by-step explanation:
The action by the billing and coding specialist that prevents fraud is a) Double-checking claim accuracy. This practice helps ensure that claims are submitted correctly, reflecting the actual services provided. It also reduces the likelihood of errors that may cause fraudulent claims or unintentional claims abuse. Double-checking can reveal discrepancies or unusual patterns that may indicate fraudulent activities. As a result, this action aligns with compliance regulations and helps maintain the integrity of the healthcare billing process.