Which statement best expresses the central idea of the excerpt? Major Tallmadge developed a unique code system so that the Americans could send secret messages. Major Tallmadge did not trust anyone with his codes other than Woodhull, Townsend, and General Washington. The number codes used in secret messages were assigned only to members of the Culper Ring. The code system Major Tallmadge designed did not work because some words did not have a number code.