What letters preceding the management code in a phrase are readily identified as management notices?

The letters that are readily identified as management notices are "MSG." This abbreviation stands for "Management Special Guidance," which indicates important directives or notices concerning management tasks and responsibilities. The term is commonly used in various management contexts, particularly in materiel management, where maintaining clarity on directives is crucial for operational efficiency.

The other options do not carry the same standard meaning in management contexts. For instance, "MGT" may suggest management in a broader sense but is not specifically tied to management notices. "MTG" typically refers to "meeting," which does not pertain directly to management notices. "MAN" is an abbreviation that could refer to manual or management in a more general term but lacks the direct association with notices like "MSG." Understanding these distinctions is important for navigating management communications effectively.