Explanation:

Kaziranga National Park is located in the State of Assam and covers 42,996 Hectare (ha).

• It is the single largest undisturbed and representative area in the Brahmaputra Valley floodplain.
• It was declared as a National Park in 1974.
• It has been declared a Tiger Reserve since 2007. It has a total tiger reserve area of 1,030 sq km with a core area of 430 sq. km.
• Kaziranga National Park was declared a UNESCO World Heritage Site in 1985.
• It is also recognized as An Important Bird Area by Bird Life International.
• It is home to the largest number of one-horned rhinos in the world.
• Pobitora Wildlife Sanctuary has the highest density of one-horned rhinos in the world and second highest number of Rhinos in Assam after Kaziranga National Park.

Hence both statements 1&3 are correct.