The overall protonproton cycle is equivalent to 21 H rightar

The overall proton-proton cycle is equivalent to: 2^1 H rightarrow H 4^1 H rightarrow H 4^1 H rightarrow H + 4n 4^1 H + 2e^- rightarrow He + 2v + 6y 4^1 H + 2e^+ rightarrow He + 2v

Solution

The answer is d) because it is equivalent to

4p 4He + 2e⁺ + 2_e

_{with positrons converting to electrons when taken to the left hand side.}