Which sport is specifically designated for individuals with mobility impairments who participate in cross-country skiing?

The correct answer is specifically designated for individuals with mobility impairments who engage in cross-country skiing is Para Nordic skiing. This sport is tailored for athletes who may have limited mobility, allowing them to compete in cross-country skiing events with adaptations that accommodate their specific needs. The term "Nordic" refers to skiing styles that include both cross-country skiing and biathlon.

Para Nordic skiing not only provides the opportunity for competition but also emphasizes inclusivity within the sport, adapting equipment and techniques such as sit-skis or poling techniques for athletes with different levels of impairment.

The other options do involve athletes with disabilities, but they are not specifically related to cross-country skiing: Para snowboarding focuses on snowboarding events for para-athletes; sledge hockey is a distinctive sport on ice played by athletes using sledges; and wheelchair curling is played on a curling sheet but does not involve skiing. These sports have their own unique structures and classifications but do not fall under the category of cross-country skiing for individuals with mobility impairments.