Fact 1: Dropping an object into water causes vibrations in the water.

Fact 2: Lake water visibly disturbed.

Given the two facts above, answer the question "Dropping an object into a lake causes what?" with the following options: 
- replication
 - Heat energy
 - vibrations
 - magnetism
 - flooding
 - contamination
 - Pollution
 - nourishment


 

   vibrations      