What was thomas malthus’s contribution to natural selection?
a. the theory that environmental resources increase in response to population pressures
b. the theory that the earth’s old age is based on geologic evidence resulting from cataclysmic events
c. the observation that an abundance of food would allow a population to increase geometrically and indefinitely, but there simply is not enough food so populations are limited by food supply
d. the binomial taxonomic system of naming species

c. the observation that an abundance of food would allow a population to increase geometrically and indefinitely, but there simply is not enough food so populations are limited by food supply

Explanation:

Darwin, in his studies of natural selection, points to the influence of the ideas of the English vicar Thomas R. Malthus in the elaboration of the concept of natural selection. In 1798 Malthus suggested that the main cause of human misery was the mismatch between population growth and food production. He said: “The power of the population is infinitely greater than the power of the earth to produce the means of subsistence for man. If the population does not encounter obstacles, it grows according to an arithmetic progression ”.

Malthus did not refer only to human populations, but tried to imagine humanity subjected to the same general laws governing populations of other species of living beings. This was one of the merits of his work, which drew Darwin's attention to the ideas of 'struggle for life' and 'survival of the fittest'.

Thus, we can conclude that the observation that an abundance of food would allow a population to increase geometrically and indefinitely, but there is simply not enough food for populations to be limited by food supply, was Malthus's contribution to the concept of natural selection.

the real answer is b. scintillation counter

"a.) well–developed vascular system."