Please use the following link to view the journal article in order to answer the following question:

https://doi.org/10.1556/2006.4.2015.010

(PLEASE MAKE SURE YOU VIEWING THE CORRECT ARTICLE BEFORE ANSWERING CALLED:

Relationship of smartphone use severity with sleep quality, depression, and anxiety in university students BY KAD?R DEM?RC?*, MEHMET AKGNL and ABDULLAH AKPINAR)

Question:

Which of the following study characteristics contribute to decreased internal validity in this study: C] It's cross-sectional 0 It's non-experimental C] It includes depressed and non-depressed people E] It includes males and females