Which statement is true by angle addition postulate?
a. 𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐴𝑂𝐷
b. 𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐵𝑂𝑃 = 𝑚∠𝐴𝑂𝑃
c. 𝑚∠𝐵𝑂𝑃 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐵𝑂𝐷

The correct answer is: 2 is true

• Step by step explanation: 
• Step 1:
• given

𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐴𝑂𝐷
From above figure, it is clear that
𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐶𝑂𝐷 does not make complete angle.

 ∴ 𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐴𝑂𝐷

• Step 2: 

𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐵𝑂𝑃 = 𝑚∠𝐴𝑂𝑃
From above figure, it is clear that

𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐵𝑂𝑃 = 𝑚∠𝐴𝑂𝑃

∴ 𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐵𝑂𝑃 = 𝑚∠𝐴𝑂𝑃

• Step 3:

𝑚∠𝐵𝑂𝑃 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐵𝑂𝐷
From above figure, it is clear that

𝑚∠𝐴𝑂𝐵 + 𝑚∠𝐶𝑂𝐷 + 𝑚∠𝐶𝑂P = 𝑚∠𝐴𝑂𝐷.

 ∴ 𝑚∠𝐵𝑂𝑃 + 𝑚∠𝐶𝑂𝐷 = 𝑚∠𝐴𝑂

• Final Answer:

Hence, statement 2 is true.