Who among the following individuals is most likely eligible to receive workers' compensation benefits?

a$.$ Gina, who hurt her back while skiing on a family vacation and is unable to perform her work as a delivery truck driver

b$.$ Ethan, who injured his right hand while fixing a machine at his company's production plant

c$.$ Nora, who was terminated without just cause and filed a discrimination lawsuit against her employer

d$.$ Howard, who was denied full retirement benefits after he retired from his job at the age of $67$