A. catalase-positive

A. catalase-positive means that the bacteria can produce an enzyme called catalase. This enzyme helps break down hydrogen peroxide, a harmful byproduct that can form during bacterial metabolism, into harmless substances like water and oxygen. When tested, bacteria that are catalase-positive will produce bubbles when hydrogen peroxide is added, indicating they have this enzyme. This characteristic is useful for identifying certain bacteria, especially in medical and laboratory settings, as it helps distinguish between different types of bacteria based on their ability to break down hydrogen peroxide efficiently.