In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[Q]: Antigens illicit the release of what in the body?, Context: The humoral (antibody) response is defined as the interaction between antibodies and antigens. Antibodies are specific proteins released from a certain class of immune cells known as B lymphocytes, while antigens are defined as anything that elicits the generation of antibodies ("anti"body "gen"erators). Immunology rests on an understanding of the properties of these two biological entities and the cellular response to both.
[A]: antibodies


[Q]: Where were the African slaves headed to?, Context: Guinea-Bissau was once part of the kingdom of Gabu, part of the Mali Empire; parts of this kingdom persisted until the 18th century. Other parts of the territory in the current country were considered by the Portuguese as part of their empire. Portuguese Guinea was known as the Slave Coast, as it was a major area for the exportation of African slaves by Europeans to the western hemisphere. Previously slaves had been traded by Arabs north to the northern part of Africa and into the Middle East.
[A]: the western hemisphere


[Q]: What kept Chopin from receiving his piano?, Context: On 3 December, Chopin complained about his bad health and the incompetence of the doctors in Majorca: "Three doctors have visited me ... The first said I was dead; the second said I was dying; and the third said I was about to die." He also had problems having his Pleyel piano sent to him. It finally arrived from Paris in December. Chopin wrote to Pleyel in January 1839: "I am sending you my Preludes [(Op. 28)]. I finished them on your little piano, which arrived in the best possible condition in spite of the sea, the bad weather and the Palma customs." Chopin was also able to undertake work on his Ballade No. 2, Op. 38; two Polonaises, Op. 40; and the Scherzo No. 3, Op. 39.
[A]:
the sea, the bad weather and the Palma customs