JEE Math Practice Question

In a workshop, there are five machines and the probability of any one of them to be out of service on a day is $${{1 \over 4}}$$ . If the probability that at most two machines will be out of service on the same day is $${\left( {{3 \over 4}} \right)^3}k$$, then k is equal to :

1. A.$${{{17} \over 4}}$$
2. B.$${{{17} \over 2}}$$
3. C.$${{{17} \over 8}}$$
4. D.4