The phrase "survival of fittest" for the first time was coined by

The correct option is B Spencer

Charles Darwin published, 'On the Origin of Species' which included the oft misquoted line 'survival of the fit.' Fit, not fittest, was originally written.

The idea here was that one merely needed to be fit enough to reproduce to pass on its genetics in the form of a new generation.

Herbert Spencer was a 19${}^{th}$-century philosopher and social idealist. He was known to be a strong supporter of Darwin's methods of evolution and a supporter of the evolutionary process by way of his writings and critiques of others. As mentioned already, Darwin published the oft-misquoted line of 'survival of the fit.' Herbert Spencer would take this concept and begin to apply it in other ways, using evolutionary theory as a means to understand the world in which he lived.

Herbert Spencer's works modified the line, making it 'survival of the fittest.' This idea and quote were then used as the foundation for what would become known as Social Darwinism.