Scott $(39)$ and Marlene $(40)$ are married, and both are the parents of Seth $(9).$ They all lived together until Marlene moved out on October $1.$ Seth stayed in the home with Scott every night for the remainder of the year. Marlene earned $$42,000$ during the year, and Scott earned $$33,000.$ Scott and Marlene file separate returns. All are U$.$S$.$ citizens, and all of Seth's support is provided by both of his parents. If each one tries to claim Seth as a dependent, per the tiebreaker rules, who is entitled to do so$?$

Scott.

Marlene.

Neither, since they each have to file married filing separately $($MFS$).$

Not enough information is given to make this determination.