A. flows
B. will be flowing
C. is flowing
D. has flowed
Sentence is in Future continuous tense.
Rule :
Subject + will/shall + be + V-ing + other agents.
A. flows
B. will be flowing
C. is flowing
D. has flowed
Sentence is in Future continuous tense.
Rule :
Subject + will/shall + be + V-ing + other agents.