Which of the following is an example of speciation? Two species of monkeys are separated by a mountain range. One species becomes short-haired, and the other becomes long-haired.

A harmless snake evolved coloration similar to a poisonous snake to avoid predators.

A single species of anole lizards evolved into 150 closely related lizard species.

Over years of breeding, dogs have evolved vastly different traits, from Chihuahuas to Saint Bernards.

Sympatric speciation is one of three traditional geographic modes of speciation.[2][3] Allopatric speciation is the evolution of species caused by the geographic isolation of two or more populations of a species. In this case, divergence is facilitated by the absence of gene flow. Parapatric speciation is the evolution of geographically adjacent populations into distinct species. In this case, divergence occurs despite limited interbreeding where the two diverging groups come into contact. In sympatric speciation, there is no geographic constraint to interbreeding. These categories are special cases of a continuum from zero (sympatric) to complete (allopatric) spatial segregation of diverging groups.[3]

In multicellular eukaryotic organisms, sympatric speciation is a plausible process that is known to occur, but the frequency with which it occurs is not known.[4] In bacteria, however, the analogous process (defined as "the origin of new bacterial species that occupy definable ecological niches") might be more common because bacteria are less constrained by the homogenizing effects of sexual reproduction and are prone to comparatively dramatic and rapid genetic change through horizontal gene transfer.

last is the correct

maybe

not sure