**Core Concept**
DNA replication is a crucial cellular process that ensures the accurate transmission of genetic information from one generation of cells to the next. It involves the unwinding of the double helix structure, the synthesis of a new complementary strand, and the formation of a new double helix with the original template strand.

**Why the Correct Answer is Right**
The correct answer is D. All of the above, as DNA replication indeed follows the semi-conservative model, forms sister chromatids, and adheres to the base pair rule. The semi-conservative model, proposed by Matthew Meselson and Franklin Stahl, suggests that the original DNA molecule is conserved in one strand of the new double helix, while the other strand is newly synthesized. Sister chromatids are formed during DNA replication, where two identical copies of the same DNA molecule are produced, attached at the centromere. The base pair rule, which states that adenine (A) pairs with thymine (T) and guanine (G) pairs with cytosine (C), is essential for DNA replication, as it ensures the accurate transfer of genetic information.

**Why Each Wrong Option is Incorrect**
**Option A:** While the semi-conservative model is the prevailing theory of DNA replication, the other options are also correct, making this choice incomplete.
**Option B:** Sister chromatids are indeed formed during DNA replication, but this option does not address the semi-conservative model or the base pair rule.
**Option C:** The base pair rule is crucial for DNA replication, but this option does not account for the semi-conservative model or the formation of sister chromatids.

**Clinical Pearl / High-Yield Fact**
During DNA replication, the enzyme helicase unwinds the double helix, and the enzyme DNA polymerase synthesizes the new complementary strand. It's essential to remember that DNA replication is a highly regulated process that involves multiple enzymes and proteins to ensure accurate and efficient transmission of genetic information.

**✓ Correct Answer: D. All of the above**