【单选题】

Questions 150-152 refer to the following article.

JetaAir Lines plans to (150) a ban on smoking on its flights as of June. Jeta’s decision is the first and unusual move among many major carriers (151) prohibit smoking on international and domestic routes.
Jeta said the removal was made in response to passenger demand; the airline is sure that it will attract more than enough new smoking customers to offset the loss of passengers who want to be free from smoke while they fly. Jeta will continue to allow smoking on its flights (152) it completes another passenger survey.
A、unless
B、yet
C、still
D、until