In a factory, 20 workers start working on a project of packing consign-
ments. They need exactly 5 hours to pack one consignment. Every hour
4 new workers join the existing workforce. It is mandatory to relieve a
worker after 10 hours. Then the number of consignments that would be
packed in the initial 113 hours is
(A) 40
(B) 50
(C) 45
(D) 52.