Answer:
The correct answer is- Aerobic activities
Step-by-step explanation:
Aerobic activities are the activities that are known as cardio exercise as it is involved in oxygenated blood pumping from the heart to the working and exhausting muscles.
Aerobic exercise is important for a long-distant runner because it improves the runner's ability to utilize oxygen so that his muscles can generate enough power to sustain him in the run for a longer time.
Some of the aerobic exercise are running, skipping, cycling, swimming, hiking, kickboxing. Therefore aerobic activities are the activity that would be the most appropriate for a long-distant runner to achieve his goal in a cross-country run.