The correct answer is B. To help the reader understand the difficult decisions faced by the Mission Control.
Step-by-step explanation
The text focuses on the dilemma that Mission Control was facing given that they had to decide on the amount of fuel for the spacecraft, because if it had a lot of fuel the weight influenced the takeoff of the ship, so it was necessary to have the right measure so they did not run out of fuel, which could be dangerous. According to the above, the author is using the problem-solution structure because he explains the problem about the Mission Control decision in which the weight of the ship and the fuel are involved to make the takeoff and later he establishes a solution for that problem by explaining how this dilemma ws solved. Therefore, the correct answer is B. To help the reader understand the difficult decisions faced by the Mission Control.