Select the correct statement from the following:

Question

$\begin{array}{1 1} \text{a. Darwinian variations are small and directionless.} \\ \text{b. Fitness is the end result of the ability to adapt and get selected by nature.} \\ \text{c. All mammals except whales and camels have cervical vertebrae.} \\ \text{d. Mutations are random and directionless.} \end{array}$