Answer:
A. digital device and screen size.
Explanation:
A "responsive design" for mobile applications is a design that responds to a user's digital device and screen size.
In Computer programming, a responsive web design makes it possible for various websites to change layouts in accordance with the user's digital device and screen size.
Hence, an end user's behavior and environment influences the outcome of their content and layout in a responsive design for mobile applications and websites.
<em>This ultimately implies that, a responsive design is a strategic approach which enables websites to display or render properly with respect to the digital device and screen size of the user. </em>
