Answer:
B. Improvements in climbing gear
Explanation:
Denali is the highest mountain in the USA and is one of the most difficult to climb. The difficulty of climbing is mainly due to the inhospitable climate, composed of very low temperatures that hinder the survival of climbers. In addition, the mountain has numerous very steep vertical climbs that make climbing extremely difficult. However, the number of people who try to climb this mountain is much greater than the number of people who tried to do it in the last century. This is probably a result of the advancement of climbing techniques and equipment, which has become increasingly safe and efficient in helping difficult mountain climbs like Denali.
