The correct answer is B . The client wants to replace email and mandatory meetings with Slack channel updates, but they are concerned employees may miss important information. An org-wide default channel that is required is the best match because it ensures employees are automatically placed into the channel and cannot treat the channel as merely optional. This supports broad communication reach and reduces the risk of employees missing periodic updates. Option A is insufficient because an optional default channel does not fully address the concern that employees may miss updates. Option C, a multi-workspace public channel, may distribute communication across workspaces, but it does not by itself guarantee that all relevant employees are included or required to remain. Option D is close but less precise; the tested Slack channel type is specifically an org-wide default channel marked required. For enterprise communications, channel strategy must balance visibility, membership enforcement, and message discipline. A required org-wide default channel provides the strongest controlled communication path.

Reference topic: Channel Strategy — org-wide channels, default channels, required membership, executive communications, and reducing email/meeting dependency.

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