In this passage one person choose to worry and be anxious, the other to stop and listen to Jesus and what He is speaking. It is hard to stop what we are doing and just listen. Just to stop and listen to Jesus is the good portion that Mary choose.
Luke 10:41-42 but the Lord answered her, “Martha, Martha, you are anxious and troubled about many things, 42 but one thing is necessary. Mary has chosen the good portion, which will not be taken away from her.”