If a father or his two daughters or his three sons can finish a work in 88 days, then how many days will Father, a daughter and a son together take to finish the same work?

Father's rate: 1/88 per day. Two daughters together: 1/88 per day, so one daughter = 1/176 per day. Three sons together: 1/88 per day, so one son = 1/264 per day. Working together: Father + daughter + son = 1/88 + 1/176 + 1/264 = (3+1.5+1)/264 = 5.5/264 = 1/48. So they complete the work in 48 days, which matches option C.