"Elephant is a slowest breeder becoming sexually matured at the age of 30, having a large gestation period. A single female reproduces by an average 6 young ones during its lifetime. If all the young ones of a pair survive, there would be 19 million descendants at the end of the 750 years" this is an example for:

(1) Mendelian theory of inheritance
(2) Part of the Darwin's theory Over production
(3) Mutation
(4) Inheritance of acquired characters