Higher organisms have resorted to sexual reproduction in spite of its complexity. Why?

(N/A) Although sexual reproduction involves more time and energy,higher organisms have resorted to sexual reproduction in spite of its complexity.
This is because this mode of reproduction helps introduce new variations in progenies through the combination of the $DNA$ from two (usually) different individuals.
These variations allow the individual to cope with various environmental conditions and thus,make the organism better suited for the environment.
Variations also lead to the evolution of better organisms and therefore,provide better chances of survival.
On the other hand,asexual reproduction does not provide genetic differences in the individuals produced.