Even if Kyle Shanahan was the type to leave his work at the office, he’s been unable to avoid discussion of his 9-to-5 job when he’s been at home recently. That’s because his wife, Mandy, is like the beat writers covering the team. She’s been hounding her husband with what’s become the most compelling question in an 0-9 season: When will Jimmy Garoppolo make his first start? “I know everyone is very excited and wants to see him play,” Shanahan said. “Including myself. Including our coaches and players. Including my wife. I get that. I’m very well aware of that.” The bad news for Mandy, and others eager to see the presumptive franchise quarterback take his first snap with the 49ers: Shanahan said he expects rookie C.J. Beathard to start Sunday against the Giants with Garoppolo serving as the backup for the second straight week. Shanahan said Garoppolo has made significant progress absorbing the playbook. Last week, the 49ers considering promoting Nick Mullens from the practice squad, but by Friday night Shanahan felt Garoppolo had learned enough to serve as the backup.