Task: Question Answering
Input (English): Passage: At the time of the transfer of power, the state of Jammu and Kashmir (widely called "Kashmir") was ruled by Maharaja Hari Singh, a Hindu, although the state itself had a Muslim majority. Hari Singh was equally hesitant about acceding to either India or Pakistan, as either would have provoked adverse reactions in parts of his kingdom. He signed a Standstill Agreement with Pakistan and proposed one with India as well, but announced that Kashmir intended to remain independent. However, his rule was opposed by Sheikh Abdullah, the popular leader of Kashmir's largest political party, the National Conference, who demanded his abdication.Pakistan, attempting to force the issue of Kashmir's accession, cut off supplies and transport links. The chaos in Punjab resulting from Partition had also severed transport links with India, meaning that Kashmir's only links with the two dominions was by air. Rumours about atrocities against the Muslim population of Poonch by the Maharajah's forces caused the outbreak of civil unrest. Shortly thereafter, Pathan tribesmen from the North-West Frontier Province of Pakistan crossed the border and entered Kashmir. The invaders made rapid progress towards Srinagar. The Maharaja of Kashmir wrote to India, asking for military assistance. India required the signing of an Instrument of Accession and setting up an interim government headed by Sheikh Abdullah in return. The Maharaja complied, but Nehru declared that it would have to be confirmed by a plebiscite, although there was no legal requirement to seek such confirmation.Indian troops secured Jammu, Srinagar and the valley itself during the First Kashmir War, but the intense fighting flagged with the onset of winter, which made much of the state impassable. Prime Minister Nehru, recognising the degree of international attention brought to bear on the dispute, declared a ceasefire and sought UN arbitration, arguing that India would otherwise have to invade Pakistan itself, in view of its failure to stop the tribal incursions. The plebiscite was never held, and on 26 January 1950, the Constitution of India came into force in Kashmir, but with special provisions made for the state. India did not, however, secure administrative control over all of Kashmir. The northern and western portions of Kashmir came under Pakistan's control in 1947, and are today Pakistan-administered Kashmir. In the 1962 Sino-Indian War, China occupied Aksai Chin, the north-eastern region bordering Ladakh, which it continues to control and administer. 
Question: What was the last name of the person who was a popular leader of the National Conference?
Output (English): Abdullah.