Answer:
b just took the test
to create pleasing sounds in the second line.
It is I have come.
present simple I / you / we / they come
he / she / it comes
past simple came
past participle come
-ing form coming
The correct answer is a.: specific.
This structure (this +adj) requires an adjective and the only adjective is in a., the other options are verbs or nouns and are not correct.