Final answer:
Mount Everest is the highest obstacle on the chart and it is the highest mountain in the world, standing at 29,028 feet (8,848 meters).
Step-by-step explanation:
The highest obstacle on the chart is Mount Everest, option A. Mount Everest is the highest mountain in the world, standing at 29,028 feet (8,848 meters). It is located in the Himalayas on the border between China and Nepal. Its height presents many challenges to climbers, including low oxygen levels and difficulties in boiling water at high altitudes.