Selected accounts with a credit amount omitted are as follows

Work in Process
Apr. 1 Balance 6,100 Apr. 30 Goods finished X
30 Direct materials 61,100
30 Direct labor 191,300
30 Factory overhead 57,390
Finished Goods
Apr. 1 Balance 14,200
30 Goods finished 306,600
What was the balance of Work in Process as of April 30?
a.$57,390
b.$9,290
c.$306,600
d.$14,200