Answer:
D). Declare the causes.
Step-by-step explanation:
In the given excerpt from the Declaration of Independence, the phrase 'declare the causes' of separation is the key purpose of the document. It logically explains that what the writer Jefferson intends to convey through the document and i.e. to explain that 'when people find it necessary to 'dissolve the political bands' and they decide to split off from them, It is their duty to announce the causes which are leading to this separation' and that is the key idea of the declaration of America's independence and separation from Britain. Thus, option D is the correct answer.