Which mountain range is found to the west of Oahu?

The Waianae Mountains are indeed the mountain range located to the west of Oahu. This range is notable for its rugged terrain and volcanic origin. The peaks within the Waianae Mountains are among the highest on the island, with Mount Kaala being the tallest. This mountain range is recognized for its rich biodiversity, beautiful hiking trails, and stunning views of the surrounding areas, making it a prominent feature of the island’s landscape.

The Koolau Mountains, while significant, are located to the east of Oahu and are not a correct choice for a westward location. The Anuenue Mountains is not a recognized mountain range on Oahu, and therefore doesn't apply. Although the Kaala Mountains reference could lead to some confusion since that is the name of the highest peak in the Waianae range, it’s not the commonly used name for the entire mountain range itself. Thus, the Waianae Mountains are correctly identified as the range found to the west of Oahu.