Step 1: Understanding the Concept:
Everett Rogers' adopter categorization identifies socioeconomic and communication characteristics of adopter categories.
Step 2: Detailed Explanation:
According to Everett Rogers' Diffusion of Innovations:
1. Early Adopters ($13.5\%$ of population): Are respected local community leaders with higher formal education, higher socioeconomic status, greater social participation, and extensive mass media exposure compared to late adopters. Hence, Statement I is true.
2. Opinion Leadership: Early adopters hold the highest degree of opinion leadership in most social systems. Potential adopters look to them for advice and trusted evaluation before adopting an innovation. Hence, Statement II is true.
Step 3: Final Answer:
Therefore, Both Statement I and Statement II are true, matching option (A).