Fact 1: Muscle contraction occurs when muscle fibers get shorter.

Fact 2: Fibers are oriented diagonally across fiber.

Given the two facts above, answer the question "muscle contraction occurs when a diagonally oriented part of muscle gets what?" with the following options: 
- shorter
 - longer
 - vertical
 - decreases
 - resistance
 - muscles
 - movement
 - forces


 

 shorter        