Question: In between Azolla and Platycarya which one is native to eastern Asia in China, Korea, and Japan?
Context: Azolla (mosquito fern, duckweed fern, fairy moss, water fern) is a genus of seven species of aquatic ferns in the family Salviniaceae.  They are extremely reduced in form and specialized, looking nothing like other typical ferns but more resembling duckweed or some mosses. Platycarya is a genus of flowering plants in the family Juglandaceae, usually treated as comprising a single species Platycarya strobilacea, though one to two additional species are accepted by some authors.  It is native to eastern Asia in China, Korea, and Japan. The East Asian–Australasian Flyway is one of the world's great flyways.  At its northernmost it stretches eastwards from the Taimyr Peninsula in Russia to Alaska.  Its southern end encompasses Australia and New Zealand.  Between these extremes the Flyway covers much of eastern Asia, including China, Japan, Korea, South-East Asia and the western Pacific.  It is especially important for the millions of migratory waders or shorebirds that breed in northern Asia and Alaska and spend the non-breeding season in South-East Asia and Australasia.  In total, the flyway passes through 22 countries with approximately 55 migratory species travelling along it, equating to about 5 million birds. The yellow-rumped flycatcher, Korean flycatcher or tricolor flycatcher ("Ficedula zanthopygia") is a species of flycatcher found in eastern Asia.  A distinctive species with almost no look-alike other than the narcissus flycatcher.  It breeds in eastern Asia including parts of Mongolia, Transbaikal, southern China, Korea and western Japan.  They winter in parts of the Malay Peninsula and South Asia. Sorbus alnifolia (syn.  "Aria alnifolia"), also called alder-leafed whitebeam, Korean whitebeam, or Korean mountain ash, , is a species of whitebeam native to eastern Asia in eastern and northern China, Taiwan, Korea and Japan. Macropodus is a genus of fairly small gouramies native to freshwater habitats in eastern Asia.  Most species are restricted to southern China (including Hong Kong and Taiwan) and Vietnam, but "M. opercularis" occurs as far north as the Yangtze basin, and "M. ocellatus" occurs north to the Amur River, as well as in Japan and Korea.  In China, they are often used for fights, so they are named Chinese bettas because of their similarity to the "Betta" genus.  A few species in the genus are regularly seen in the aquarium trade, and "M. opercularis" has been introduced to regions far outside its native range. Hydrangea ( ; common names hydrangea or hortensia) is a genus of 70–75 species of flowering plants native to southern and eastern Asia (China, Japan, Korea, the Himalayas, and Indonesia) and the Americas.  By far the greatest species diversity is in eastern Asia, notably China, Japan, and Korea.  Most are shrubs 1 to 3 meters tall, but some are small trees, and others lianas reaching up to 30 m by climbing up trees.  They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous. Zelkova serrata (Japanese zelkova, Japanese elm or keyaki; Japanese: 欅 (ケヤキ) "keyaki" /槻 (ツキ) "tsuki" ; ; Korean: 느티나무 "neutinamu" ) is a species of the genus "Zelkova" native to Japan, Korea, eastern China and Taiwan.  It is often grown as an ornamental tree, and used in bonsai.  There are two varieties, "Zelkova serrata" var.  "serrata" in Japan and mainland eastern Asia, and "Zelkova serrata" var.  "tarokoensis" (Hayata) Li on Taiwan which differs from the type in its smaller leaves with less deeply cut serration on the margins. Pinus koraiensis is a species of pine known commonly as the Korean pine.  It is native to eastern Asia: Korea, northeastern China, Mongolia, the Temperate rainforests of the Russian Far East, and central Japan.  In the north of its range, it grows at moderate altitudes, typically 600 m to 900 m , whereas further south, it is a mountain tree, growing at 2,000 m to 2,600 m altitude in Japan.  Other common names include Chinese pinenut. Azolla pinnata is a species of fern known by several common names, including mosquitofern, feathered mosquitofern and water velvet.  It is native to much of Africa, Asia (Brunei Darussalam, China, India, Japan, Korea, and the Philippines) and parts of Australia.  It is an aquatic plant, its frond floating upon the surface of the water.  It grows in quiet and slow-moving water bodies, because swift currents and waves break up the plant.
Answer: Platycarya