Which of the following statements are true? Select all that apply.
In a triangle ABC, angle A is (2x + 1) degree, angle B is x degree, and angle C is (x + 15) degree.
A. (4x + 16)° = 180°
B. x° = 49°
C. m∠A = 99°
D. From smallest to largest: ∠B, ∠C, ∠A