At a ship the food was enough for 50 people. But after 10 days half of the men died due to some viral disease and the food is sufficient for as long as before. How long the food was sufficient for then?

At a ship the food was enough for 50 people. But after 10 days half of the men died due to some viral disease and the food is sufficient for as long as before. How long the food was sufficient for then?

A. 20
B. 60
C. 70
D. 50