Final answer:
Beta-lactamase-producing bacteria are gram-negative rods resistant to penicillins, cephalosporins, and monobactams due to enzymes that disrupt the ß-lactam ring. Extended-spectrum ß-lactamase (ESBL) provides resistance to a broader range but not carbapenems.
Step-by-step explanation:
The correct answer to the question is A) Beta-lactamase-producing bacteria. These bacteria are gram-negative rods that are resistant to a wide range of antibiotics, including all penicillins, cephalosporins, and monobactams due to the production of beta-lactamase enzymes. These enzymes are able to cleave the ß-lactam ring present in these antibiotics, rendering them ineffective. Extended-spectrum ß-lactamases (ESBLs) further complicate treatment by providing resistance to an even broader spectrum of ß-lactam antibiotics, although not generally to carbapenems.
It's important to note that the resistance is due to the breakdown of antibiotics by the beta-lactamase enzyme, which can cleave the ß-lactam ring that is central to the antibiotic's mechanism of action. Alterations and addition of side chains to the base structure of ß-lactam antibiotics can increase their resistance to ß-lactamase degradation, providing a broader spectrum of activity against bacteria.