Why Would a President Ask Members of Congress to Endorse

Why would a president ask members of Congress to endorse a military action two months after it was launched, even though she or he is the constitutional commander in chief of the armed forces?

A) The Constitution requires that Congress approve any military troops being overseas within two months of deployment.
B) The Supreme Court justices have previously ruled that Congress must have a say in all military actions in order for them to be constitutional.
C) The War Powers Act requires a president to gain congressional approval for the use of force within 90 days.
D) Executive agreements such as sending troops into another country require two-thirds of the Senate to approve.