**Core Concept**
The development of dentin bonding agents has revolutionized restorative dentistry by allowing for the creation of durable, long-lasting restorations. These agents work by forming a strong bond between the dentin and the restorative material, thereby preventing microleakage and secondary caries.

**Why the Correct Answer is Right**
The first dentin bonding agent to receive ADA acceptance was Scotchbond, developed by 3M. This agent utilizes a two-step etch-and-rinse technique, first etching the dentin surface with phosphoric acid to create microporosities and then applying a silane coupling agent to enhance the bond between the dentin and the restorative material. The combination of etching and silanization allows for a strong, durable bond that resists degradation and microleakage.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while it may be a well-known dentin bonding agent, it is not the first to receive ADA acceptance.
**Option B:** This option is incorrect because it is a more recent development in dentin bonding agents and did not receive ADA acceptance as the first.
**Option C:** This option is incorrect because it is primarily used as a bonding agent for enamel, not dentin.

**Clinical Pearl / High-Yield Fact**
The ADA acceptance of dentin bonding agents has significantly improved the longevity and success of restorations, making them a crucial component of modern restorative dentistry.

**Correct Answer: C. Scotchbond.