Sorry but I don’t know the answer
Survival of the strongest... an organisms strength does not affect the natural selection process. Natural selection is adapting the species to be able to better survive in its environment. In order to better survive, an organism does not to be strong. e.g. a plant is probably not a “strong” organism and natural selection doesn’t change that in most cases
It will be better for the population
Photosynthesis occurs in the Chloroplasts.
The respiration takes place in the Mitochondria.
Hope this helps!! :)