Answer:
A. Positive linear.
Explanation:
We have that both variables increases, then we have a positive relation. A curvilinear option can not be possible because with this option in some regions could happen that when one variable increases the other one decreases. The negative linear relation can no be because with this option when one variable increases the other decreases. A non linear option is the same as a curvilinear option then can not be possible. Then the best option is a positive linear relationship.