QUESTION<br/><br/>One day humans ..................on Mars if US President Bush's recently announced plans ...............to fruition.<br/><br/>a- could be walking - come<br/><br/>b-would walk - had come <br/><br/>c- can be walking - will come <br/><br/>d- would have wlked -come<br/><br/>e- will be walking - might come<br/><br/>According to you , which is the best for the blanks in the sentence above? please explain