My question involves labor and employment law for the state of: State of California

Hello,
My brother in law has a potentially wonderful job but it involves security clearance with his future employer which is in the aerospace industry.
My question is he now in 58 but 33 years ago in a different state he was incarcerated for 9 months. Will this show up?
I have posted some of the questions asked:
Have you EVER been convicted in any court of the United States of a crime, sentenced to imprisonment for a term exceeding 1 year for that crime, and incarcerated as a result of that sentence for not less than 1 year? (Include all qualifying convictions in Federal, state, local, or military court, even if previously listed on this form)
Have you EVER been charged with any felony offense? (Include those under the Uniform Code of Military Justice and non-military/civilian felony offenses)
He doesn't know how to quite answer it since this happened 33 years ago.
Thank you for you help.