Which part of the following sentence contains an error?He knew /(a) that he will / (b) go back / (c) on his promise / (d)

Which part of the following sentence contains an error?He knew /(a) th

1.	Which part of the following sentence contains an error?He knew /(a) that he will / (b) go back / (c) on his promise / (d)
A.	(b)
B.	(c)
C.	(d)
D.	(a)
Answer» B. (c)