Suppose Host A sends four TCP segments to Host B over a TCP connection. The first segment has sequence number 0; the second has sequence number 120, the third has sequence number 170 and the last one has sequence number 245. Assume sequence number used by B starts at 0 and the messages sent from B to A contains 10 bytes of data.

If the second segment arrives before the first segment, what is the acknowledgment number in the acknowledgment segment (sent from B to A) of the first arriving segment?

A) 0 , B) 170 , C)120 , D) 10