The correct option is B Darwin
From the book "On the origin of Species" originally published in the year 1859, Darwin had described Natural Selection that was understood as "Survival of the form that will leave the most copies of itself in successive generations." Herbert Spencer, an English philosopher and biologist, read Darwin's book and observed parallelism between his own economic theories of evolution and Darwin's Natural Selection theory. In his book "Principles of Biology" (1864), Spencer describes this, and uses the phrase "survival of the fittest". Although the phrase was coined by Spencer, it was Darwin who explained the idea in his theory of Natural Selection. Alfred Wallace is known for his contribution to the theory of Natural Selection. Thomas Malthus is famous for his publication "the Principle of Population" (1798) where he made the observations that the human race would be likely to overproduce if the population size was not kept under control.