Please help me!

[PhiLongLe]

Known for his skilled retorts, William F. Buckley has been a leading conservative voice..................
a)for closely fifty years
b)for almost half a century
c)for a virtual half century
d)for baryly less than fifty years
Which is right answer, why is it right, and why the others is wrong.
Thank you very much

[Alan]

This isn't a question about the tests. Is it some other test?
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English as a Second Language
You can read my ESL story Present Simple

[Mosteque]

b is correct
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obsequium amicos, veritas odium parit