There are 61 codons that each specify the addition of a specific amino acid, and three stop codons ...

There are 61 codons that each specify the addition of a specific amino acid, and three stop codons for which there is no corresponding amino acid. However, there are only about 40 tRNA molecules, representing 40 anticodons. How is that possible?
A) Only about 40 of the recognized 61 codons are present in mRNA.
B) An anticodon forms hydrogen bonds with the codon; it must match the first two bases of the codon, but is less specific with respect to the third base.
C) There are tRNAs that can bind one of two related amino acids.
D) Only 20 of the codons are active–one for each amino acid.