Harry needs help screening TV scripts and tells Joan that, if she $$manages to stay off the sauce$($stay sober at work$),$ he will make her his department assistant. Harry hires Joan, but one day he catches her drunk at work and fires her. Can Joan sue Harry for breach of contract?

$$

a$)$ No$,$ a condition precedent triggered the duty to perform

b$)$ No$,$ a condition concurrent triggered the duty to perform

c$)$ No$,$ a condition subsequent affected performance

d$)$ Yes