The correct answer is ‘Part B’. Key Points Let’s look at the below points- In the second part of the given sentence ‘does not’ will not come with ‘until’. Until/Unless is used in place of ‘if…not’ in the conditional sentence. Until means ‘up to the time’ and it expresses the sense of ‘time’. ‘Not’ is not used with until or unless. E.g. Unless it rains, we will go for dinner. The correct sentence- We will not start the party until Ria arrives at the venue. Additional Information Until is used in the context of time and roughly means before and up to the time. Unless is used in the context of a precondition and means if this condition is not met. For example: You can't get a job until you have experience.[ alt="false (2)" src="https://storage.googleapis.com/tb-img/production/20/08/false%20%282%29.png" style=" white-space: pre-wrap; width: 25px; height: 25px;"> You can't get a job unless you have experience.[ alt="right (1)" src="https://storage.googleapis.com/tb-img/production/20/08/right%20%281%29.png" style="width: 25px; height: 25px;">