A fermentor (or bioreactor) provides controlled environmental conditions (optimum temperature, pH, aeration, agitation, and nutrient supply) for the maximum growth of microorganisms or cells to synthesize the desired metabolic products.

Inosine (I) at the 5' wobble position of the tRNA anticodon ($5'\text{-I-C-G-}3'$) can base-pair with U, C, or A at the 3' position of mRNA codons. Codons are read 5' to 3', so compatible mRNA codons pairing with $5'\text{-I-C-G-}3'$ are $5'\text{-C-G-U-}3'$, $5'\text{-C-G-C-}3'$, and $5'\text{-C-G-A-}3'$. Thus, (A) and (C) only are correctly matching codons.

Tetracycline selectively binds to the bacterial 30S ribosomal subunit and sterically blocks the entry and attachment of incoming charged aminoacyl-tRNA to the ribosomal acceptor (A) site, thereby preventing translation elongation. Reason (R) directly explains Assertion (A).