**Core Concept**
The unwinding enzyme in DNA synthesis is crucial for the initiation of replication. This enzyme helps to separate the two strands of the DNA double helix, allowing the replication machinery to access the template strands.

**Why the Correct Answer is Right**
The unwinding enzyme in DNA synthesis is indeed **Helicase**. Helicase uses the energy from ATP hydrolysis to unwind the DNA double helix, creating a replication fork. This process involves breaking the hydrogen bonds between the base pairs, allowing the replication machinery to access the template strands. Helicase is essential for the initiation of replication and is a key enzyme in the replication process.

**Why Each Wrong Option is Incorrect**
**Option B:** Primase is responsible for synthesizing RNA primers, which are necessary for the initiation of DNA synthesis. However, it is not the unwinding enzyme.
**Option C:** DNA Polymerase is responsible for synthesizing new DNA strands by adding nucleotides to the growing chain. While it is involved in DNA synthesis, it is not the unwinding enzyme.
**Option D:** Transcriptase is an enzyme involved in the synthesis of RNA from a DNA template, and is not involved in DNA synthesis.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the unwinding of DNA is a crucial step in the replication process, and that helicase plays a key role in this process. This knowledge is important for understanding the replication process and the enzymes involved.

**✓ Correct Answer: A. Helicase**