Answer: A. Usability testing
Explanation:
Usability testing would be the correct answer because if the user interface isn't "frendly" then people won't be able to use it properly. Or if you are refering to the word friendly as looking safe, then even more so would be usability testing. Because if people don't like the fonts and styles of the user interface, they might not use it at all.
Explanation:
Acid rain can cause serious problems for many different animals and plants. As a result, the entire food web is affected. For example, acid rain can cause phytoplankton in lakes to die. Insects, which rely on phytoplankton for food, now have less food to eat, and they begin to die as a result.
