Which statement is true regarding Clostridium perfringens?

• A. There are five serologic types.
• B. Spores are terminally located.
• C. Alpha-toxin is produced by all strains.
• D. Spores are readily seen in laboratory media.

Answer: (C)

The main idea here is that alpha-toxin is produced by all Clostridium perfringens strains. This toxin, a phospholipase C (lecithinase), is a universal virulence factor for the species, which is why the statement about alpha-toxin being produced by every strain is true. In contrast, typing of C. perfringens is based on the combination of toxins produced (the toxinotypes A through E), not serologic types, so claiming five serologic types is inaccurate. Spore formation in C. perfringens is not a reliable diagnostic feature; spores are rarely observed in routine laboratory cultures, and their location is not a defining characteristic, so statements about terminally located spores or spores being readily seen are not correct.