You Congress whenever 2/3 of both houses shall demon necessary shall propose amendments to this constitution or on the application of the legislatures of 2/3 of the several States shall call on convention for proposing amendments which in either case shall be valid to all intended and proposes as part of the Constitution using the expert to answer the question which of the following best summarizes this expert

The passage is stating that amendments to the constitution can be proposed by Congress if 2/3 of both houses deem it necessary. Alternatively, amendments can be proposed by a convention called upon the application of 2/3 of the state legislatures. In both cases, the proposed amendments will be considered valid and treated as part of the Constitution.