Answer:
A.
Step-by-step explanation:
These are group of antibiotics which effective against the gram+ and gram- bacteria,and against any bacteria causing diseases and infection. They are groups of old generation type of antibiotics.e.g tetracycline, chrloramphenicol,
They are specifically used;
When there is urgent need to suppress the effect of bacteria, where further delay could be complicating.-emergency.
Against group of bacteria which had developed antibiotic resistance to administrated antibiotics
To protect the body against bacteria infection, prior to engaging in activities or exposure to bacteria infested medium.
To protect against infection where the immune response of the individual is very low. e.g Sickle cell Anemia.
Thus Broad Spectrum were not tailored towards a specific bacteria, but against broad range of suspected bacteria.
Narrow spectrum are tailored towards a specific bacteria, thus they can not be used when there is urgent need to protect against unknown bacteria..