When the infield fly rule is not announced, is it still in effect?

The correct choice indicates that the infield fly rule remains in effect even if it is not announced. The logic behind this is rooted in the nature of the rule itself, which is designed to protect the offensive team from potential unfairness, especially in situations where a fielder could intentionally drop a catch to create a double play opportunity.

Both teams are expected to understand the conditions under which this rule applies, regardless of whether the umpire explicitly announces its enforcement. The rule serves to clarify situations where a fly ball could be caught with ordinary effort by infielders and thus creates a standard for the plays in question, ensuring that the defensive team cannot take advantage of the situation through miscommunication or intent.

This understanding is crucial, as it emphasizes that the enforcement of the rule is automatic based on the game situation, reinforcing fair play principles. The other options suggest limitations or requirements that do not align with the core intention of the infield fly rule.