Which statement about Clostridium perfringens is true?

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

Answer: (B)

Clostridium perfringens is classified into five toxinotypes (types A through E) based on the pattern of major toxins they produce, namely alpha, beta, epsilon, and iota. This five-type system reflects serologic/toxin profiling used to distinguish strains, which is why the true statement references five serologic types. Alpha toxin is produced by all strains, so that feature doesn’t differentiate the types. Spore visibility in routine lab media is not reliable for this organism, and the spores of C. perfringens are not typically a defining diagnostic feature, unlike what you’d see with some other Clostridium species where spores are terminal.