Which of the following tests can give a presumptive identification of Branhamella catarrhalis?

The beta-lactamase test is particularly significant in the presumptive identification of Branhamella catarrhalis because this bacterium is known for producing beta-lactamase enzymes. These enzymes confer resistance to a variety of beta-lactam antibiotics, including penicillins. When testing for Branhamella catarrhalis, a positive result in the beta-lactamase test indicates that the organism can break down beta-lactam antibiotics, supporting its identification.

Understanding that many other bacteria do not have this ability allows for a more straightforward approach to identification, particularly in cases where the presence of Branhamella catarrhalis is suspected. This test provides valuable information indicating resistance patterns that align with the characteristics of this organism, making it a reliable presumptive identification method.