You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).

Paragraph: By using multiple stages, empty fuel containers could drop away. This reduced the mass of the rocket so that it could fly higher.
 Question: David is getting ready to fly into space on a rocket. As the rocket shoots upwards, part of the mass attaches, allowing the rocket to go 
 Choices: A)higher 
B)lower
lower