Cetyltrimethylammonium chloride is which type of detergent?

Which of the following is not considered an antibiotic?

In the given reaction scheme,$P$ is a phenyl alkyl ether,$Q$ is an aromatic compound; $R$ and $S$ are the major products.
$P$ $\xrightarrow{HI} Q$ $\xrightarrow[\text{(iii) } H_3O^{+}]{\text{(i) } CO_2, \text{(ii) } NaOH} R$ $\xrightarrow[\text{(ii) } H_3O^{+}]{\text{(i) } (CH_3CO)_2O} S$
The correct statement about $S$ is:

Which preservative is used for the preservation of fruit juices?

Which artificial sweetener contains chlorine,tastes like sucrose,and is stable at cooking temperatures?

Which of the following is an antidepressant drug?