Answer: Muscular Endurance
Explanation: If I'm remembering the fitnessgram push-up test correctly, it's just as many push-ups you can do in a certain amount of time. Usually if it's doing something as many times as you can, it's endurance.
Ex. a deadlift, lifting something really heavy once, is muscular strength, but lifting a smaller weight 10-20 times in muscular endurance.