Correct Answer: B
Explanation:
Attain: succeed in achieving (something that one has worked for).
Crave: feel a powerful desire for (something).
Harbour: a place on the coast where ships may moor in shelter, especially one protected from rough water by piers, jetties, and other artificial structures
Credit: the ability of a customer to obtain goods or services before payment, based on the trust that payment will be made in the future
Thus option B is correct answer.