Computing in Space with the Starfishing Astronaut

It’s a great day for fishing in space! Help the astronaut “fish” for the rule that matches each set of problems. All of the input numbers in each set are either being added to or subtracted from the same number. Don’t worry! Each set has 4 possible answers given to you in multiple-choice form! Once you determine the “rule”, you’ll complete the last two output numbers in the set.