The competitor factors considered when doing a competitive analysis are:

What is the competitor diversity $-$ Do the competitors have similar goals, competencies, and assets? These markets tend to be more competitive than markets with diverse competitors because similar companies tend to target the same customers.

Competitor rationality $-$ Will the competitors be rational or not. Irrational competitors may have a history of using price wars and comparative advertising campaigns.

The number of competitors in the market space

Only a and b