Step 1: Concept
Dicarboxylic acids have specific common names.
Step 2: Meaning
Propanedioic acid has three carbons: $HOOC-CH_2-COOH$.
Step 3: Analysis
Common names follow the order: Oxalic (2C), Malonic (3C), Succinic (4C), Glutaric (5C), Adipic (6C).
Step 4: Conclusion
Hence, the correct answer is malonic acid.
Final Answer: (B)