The word that has same meaning as the italicized word in both the sentences is Option D, 'bond'. Bond means attach or bind. It also means agreement with legal force. Sentence I means that marriage is a bond between two souls and not only a physical and social meeting of two individuals. Sentence II means that they have executed a bond to transfer their property rights in favour of organization. Option A, 'harmony' means a situation in which people are peaceful and agree with each other. Option B, 'Unison' means simultaneously. Option D, 'treaty' is a written agreement, formally approved and signed by their leaders. Thus, options A, B and D are incorrect and the word that fits in both the given sentences is option C, bond'.