**Core Concept**
Degeneracy in the genetic code refers to the phenomenon where multiple codons (sequences of nucleotides) code for the same amino acid. This means that the same amino acid can be represented by more than one codon, resulting in redundancy in the genetic code.

**Why the Correct Answer is Right**
The genetic code is composed of 64 possible codons, which are formed by combinations of 4 nucleotides (adenine, guanine, cytosine, and thymine) in sequences of 3. However, only 20 amino acids are encoded by these codons. This is due to the degeneracy of the genetic code, where multiple codons code for the same amino acid. For example, the codons UUU and UUC both code for the amino acid phenylalanine. This redundancy is thought to provide a safeguard against errors in protein synthesis and to allow for some flexibility in the genetic code.

**Why Each Wrong Option is Incorrect**
**Option A:** Transcription refers to the process of creating a complementary RNA copy from a DNA template. It is not related to the concept of degeneracy in the genetic code.
**Option C:** Mutation refers to a change in the DNA sequence of an organism. While mutations can result in changes to the genetic code, they do not explain the phenomenon of degeneracy.
**Option D:** Frameshift refers to a type of mutation that occurs when the reading frame of the genetic code is altered, resulting in a completely different amino acid sequence. This is not related to the concept of degeneracy.

**Clinical Pearl / High-Yield Fact**
Degeneracy in the genetic code is a fundamental concept in molecular biology, and it has important implications for our understanding of protein synthesis and the evolution of the genetic code.

**✓ Correct Answer: B. Degeneracy**