Answer:
Having extensively resistant TB means TB infection that is resistant to most the antibiotics that can be used.
Explanation:
Tuberculosis or TB is a bacterial infection produced by an alcohol-resistant bacteria, the mycobacterium tuberculosis.
Extensively resistant TB is a rare variety of the disease that is resistant to drugs commonly used in it, such as rifampicin, ethambutol and isoniazid, as well as other antibiotics such as aminoglycosides or fluoroquinolones. The denomination of this variety is extensively drug resistant tuberculosis or XDR-TB.
The other options are not correct because of:
XDR-TB is a serious public health problem, which can have serious consequences for the person who suffers from it.