B) He wants the Lilliputians to set him free.
Gulliver agrees to swear an oath to the Lilliputians in order to be set free. The Lilliputians captured Gulliver and chained him in a building. Gulliver became close to the Lilliputians Emperor and was granted a freedom petition. He was expected to take an oath to obey the stipulations given to him i.e. helping the Lilliputians during the war and surviving their lands. Gulliver agreed to all this and his chain was removed.