Answer:
The correct answer is option D.
Explanation:
Step 1: 
Step 2: 
Overall reaction can be determined by adding all the reactions of mechanism:

Reactants in an overall reaction = 
Products in an overall reaction = 
According to question , the role of oxygen gas is product.
They all have 2 elections in the outer S orbital, and 4 electrons in the P orbitals.
Answer:
ans is (2) 2,4- hexadiene
Answer:
The answer is barium phosphate