A NAVAREA warning carries the following number; 1986/87 (11). Which statement is TRUE?

Correct Answer: Option B — This is warning number 1986 issued in 1987, and it affects sub-region 11.

In standard navigational warning numbering formats, the first digits represent the sequential serial number issued within the year, followed by the year, and the parenthetical numeral indicates the specific geographic sub-region affected.