Which feature of the ocean floor results when one plate is pulled under another?

I’m doing some practice exam questions for biology, and i’m not sure how to do these 3 parts to the question.

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.

Examine the air pressure map. which type of line is shown on the map?