Avery useful group of broad-spectrum drugs, whose popularity has more recently declined because of numerous potential side effects, including keratoconjunctivitis sicca, polyarthritis (especially in doberman pinschers), hematuria, photosensitivity, and hypothyroidism, is the
a. sulfonamidesb. macrolidesc. tetracyclinesd. fluoroquinolones

a. Sulfonamides.

Explanation:

Sulfonamides drugs are used to treat infections preventing the growth of bacterias, it is an antibiotic. It was discovered in the '30s but due to its potential side effects, the use of them has decreased. Some of the side effects apart from the ones mentioned in the question are dizziness, diarrhea, skin rash, tiredness, and nausea.

well when looking at this if you think about it   negativley and positivley   react with each other and when the first layer gets full they add layers it starts with 2 on the first layer and it constantly goes on until the official number is there