Which of the following statements about mindfulness is true?

(A) Mindfulness requires a serene environment to practice.
(B) Mindfulness is another word for meditation.
(C) You can practice mindfulness during virtually any activity.
(D) A and B

(C) You can practice mindfulness during virtually any activity.

Explanation:

Mindfulness is a practice that consists of directing one's attention to the present, and of being aware of our feelings, sensations, thoughts, and our environment “here” and “now,” without being judgmental. It can be practiced during virtually any activity: while walking, running, standing, doing sports, etc. and it is recommended to practice it at least 10 minutes per day. It has proven to be beneficial to our health because it lowers anxiety and stress levels.

I'll answer this is you put the rest of the question in the comments :)