Paragraph- Sent 1: I'm here to tell you the story of a robot named Carl.
Sent  2: He came from a far away land known as Factory.
Sent  3: Carl was sad because he was missing a part called a tire.
Sent  4: He also needed a sun gatherer.
Sent  5: But, the tire was more important.
Sent  6: Once Carl got all these parts he could travel to his new home in the nation of Lab and the city of Office.
Sent  7: It was a tricky thing to get there with missing parts.
Sent  8: Just as he had given up hope Carl got a message from Mr. X saying the new parts were ready to be delivered.
Sent  9: This made the robot very happy.
Sent  10: The parts arrived a few days later and Carl put them in with 2 days of work.
Sent  11: After this Carl began to travel the last bit of his goal to get to his new job.
Sent  12: After this Carl took 10 days to get to Lab.? 
Question: Which was the most important missing part that Carl has to get after getting out of the factory?
No.