Which pair correctly categorizes interfaces as trading vs market/reference data?

Which pair correctly categorizes interfaces as trading vs market/reference data?

• A. STI, OTI, QTI are trading; IMI, MDI, RDI are market
• B. STI, QTI are trading; IMI and RDI are market
• C. OTI and QTI are market; MDI and RDI are trading
• D. STI and OTI are trading; IMI and MDI are market

Answer: (A)

Trading interfaces are those you use to actually place and manage trades, while market/reference data interfaces provide the information that supports trading but doesn’t execute orders. So you look at what each interface is meant to do: does it send orders and handle executions, or does it deliver data about instruments, prices, and metadata? The trio that handles trading includes the Securities Trading Interface for equity trades, the Options Trading Interface for options, and the Quotes Trading Interface that streams or provides quotes used during trading. These are all about enabling and supporting the act of trading itself. The remaining trio serves data needs: an Instrument Master/Instrument-related interface delivers instrument definitions and identifiers, a Market Data Interface provides live or delayed market prices and quotes, and a Reference Data Interface supplies static information such as instrument descriptions and identifiers. This set is organized around data and reference information rather than order execution. That alignment—STI, OTI, and QTI for trading, IMI, MDI, and RDI for market and reference data—best fits the intended roles, which is why it’s the correct grouping. Other pairings mix these purposes, misclassifying at least one interface.

Trading interfaces are those you use to actually place and manage trades, while market/reference data interfaces provide the information that supports trading but doesn’t execute orders. So you look at what each interface is meant to do: does it send orders and handle executions, or does it deliver data about instruments, prices, and metadata?

The trio that handles trading includes the Securities Trading Interface for equity trades, the Options Trading Interface for options, and the Quotes Trading Interface that streams or provides quotes used during trading. These are all about enabling and supporting the act of trading itself.

The remaining trio serves data needs: an Instrument Master/Instrument-related interface delivers instrument definitions and identifiers, a Market Data Interface provides live or delayed market prices and quotes, and a Reference Data Interface supplies static information such as instrument descriptions and identifiers. This set is organized around data and reference information rather than order execution.

That alignment—STI, OTI, and QTI for trading, IMI, MDI, and RDI for market and reference data—best fits the intended roles, which is why it’s the correct grouping. Other pairings mix these purposes, misclassifying at least one interface.