Which letters may be used as suffixes after an IDF code to indicate an attempt?

• A. G
• B. G, D, S, and X
• C. D
• D. S

Answer: (B)

When interpreting IDF codes, adding a suffix communicates the outcome or status of the action, such as whether an attempt was made. The suffixes that indicate an attempt are the letters G, D, S, and X. Each of these can be appended to an IDF code to show that an attempt occurred, not that the action was completed or another status applied. That’s why this set is the best answer: it includes all the suffixes used to signal an attempt. Using only a single letter would miss other valid suffixes that can also denote an attempt, so recognizing the full group G, D, S, and X is essential.