**Core Concept**
Introns are non-coding regions within a gene that need to be removed during the process of splicing to form a mature messenger RNA (mRNA) molecule. This process is crucial for the correct expression of genes.

**Why the Correct Answer is Right**
The removal of introns is facilitated by a complex called the spliceosome, which recognizes specific sequences at the intron-exon boundaries. The spliceosome then cleaves the pre-mRNA at these sites, removing the intron and joining the adjacent exons together. This process is essential for the proper processing of pre-mRNA into mature mRNA, which is then translated into a protein.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because introns are not removed by the process of transcription itself, which is the synthesis of pre-mRNA from DNA.
**Option B:** Incorrect because the process of translation, which involves the assembly of amino acids into a polypeptide chain, does not involve the removal of introns.
**Option C:** Incorrect because the process of reverse transcription, which is the synthesis of DNA from RNA, does not involve the removal of introns.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the removal of introns is a crucial step in the processing of pre-mRNA, and any defects in this process can lead to the production of aberrant or non-functional proteins, which can contribute to various diseases.

**Correct Answer: C. Spliceosome**