The correct answer is All are correct.

• The International Union for Conservation of Nature’s Red List of Threatened Species was established in 1964. 
• It provides the world's most comprehensive information source on the global extinction risk status of animal, fungus and plant species.
• The IUCN Red List is a critical indicator of the health of the world’s biodiversity. 
• White Winged Wood-duck, Red Panda, and Snow-Leopard are endangered species in India. Hence, all are correct.

• White Winged Wood-duck
  • Scientific name-Cairina scutulata
  • It was once distributed widely across north-east India and south-east Asia.
  • But now, only about 800 survive in the wild of which about 450 are present in India, Bangladesh and Myanmar.
  • In India, the duck is limited to Assam and Arunachal Pradesh.
  • It mostly resides in dense tropical evergreen forest and is known to prefer inaccessible swampy areas formed by numerous rivers, streams, etc.
• Red Panda
  • Scientific name-Ailurus fulgens
  • It is a small arboreal mammal found in the forests of India, Nepal, Bhutan and the northern mountains of Myanmar and southern China.
  • In India, it is found in Sikkim, western Arunachal Pradesh, Darjeeling district of West Bengal and parts of Meghalaya.
  • It thrives best in mixed deciduous and conifer forests with dense understories of bamboo.
• Snow-Leopard
  • Scientific name-Panthera uncia
  • They are found in 12 countries including China, Bhutan, Nepal, India, Pakistan, Afghanistan, Russia, and Mongolia.
  • It plays a key role as both top predators and as an indicator of the health of their high-altitude habitat.

• The IUCN Red List is used by government agencies, wildlife departments, and conservation-related organisations.
• It provides information about a range, population size, habitat and ecology, use and/or trade, threats, and conservation actions that will help inform necessary conservation decisions.
• In descending order of threat, the IUCN Red List threat categories are as follows:-
  • Extinct or Extinct in the Wild
  • Critically Endangered, Endangered and Vulnerable: species threatened with global extinction
  • Near Threatened: species close to the threatened thresholds or that would be threatened without ongoing conservation measures
  • Least Concern: species evaluated with a lower risk of extinction
  • Data Deficient: no assessment because of insufficient data.