Which sentence with a transition is punctuated correctly?

a. I trained hard for the marathon, however, I failed to finish.

b. I trained hard for the marathon however I failed to finish.

c. I trained hard for the marathon; however, I failed to finish.

d. I trained hard for the marathon; however I failed to finish.

often a noun phrase is just a noun or a pronoun:

people like to have money.

i am tired.

it is getting late.

what are the words supposed to be listed?

i'm thinking it would be when compound subjects are joined by or, nor,either-or, neither-nor.

perhaps, jefferson is the best spokesman that speak about american ideals of equality and liberty.

no one should be immune to the law because if there is an existence of someone that is above the law, a true equality would never be achieved

hope this

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