Read the given statements about population theories carefully and identify the correct statements.
A. Dumont believed in the prevalence of social capillarity.
B. Spencer believed that man had no control on his reproduction.
C. Sadler believed that man's nature shall inevitably lead to such a high fertility that there would be a severe conflict between his fertility and the ability to produce subsistence.
D. According to Malthus growing density could bring change in fecundity.
Choose the correct answer from the options given below: