Let S denotes the set of all real values of the parameter ‘a’ for which every solution of the inequality log1/2 x2 ≥ log1/2 (x + 2) is the solution of the inequality 49x2 – 4a4 ≤ 0. What is the value of S?

• A. (-∞, -√7) ∪ (√7, ∞)
• B. (-∞, -√7] ∪ [√7, ∞)
• C. (-√7, √7)
• D. [-√7, √7]