Rash on calves

56 y Puerto Rican woman presents to the office complaining of a non- pruritic skin rash on her calves. Apparently, she was at an arts festival over the weekend with an outside temperature of 96 degrees Fahrenheit. She acknowledges being on her feet for almost 8 hours. Her past history is significant for HTN and is stable on HCTZ and Diltiazem. On exam, she is very comfortable. Her vital signs are stable and except for an erythematous rash restricted to the calves, her exam is within normal limits.
What is the most likely diagnosis?

1. Contact dermatitis
2. Dermatophytosis
3. Superficial thrombophlebitis
4. Golfer’s vasculitis
5. Photodrug eruption
6. Polymorphous light eruption