The fossils in the La Brea Tar Pits belong to the Pleistocene epoch.
The Pleistocene epoch lasted from about 2.6 million years ago to around 11,700 years ago. It was when the climate of the Earth experienced significant fluctuations with alternating glacial and interglacial periods.
The La Brea Tar Pits are famous for preserving a diverse assemblage of prehistoric animals including saber-toothed cats, dire wolves, mastodons and giant ground sloths. These fossil was attributed to Pleistocene epoch.
These animals became trapped in the sticky asphalt deposits of the tar pits which acted as natural traps. Over thousands of years, more and more animals met their demise in these tar pits resulting in the accumulation of an extensive fossil record.
Therefore, the Option A is correct.