So what is the best backup/failsafe for an airline pilot?

Let's say our subject of example is a regional FO with a BA in an unrelated field, has low TT.

A business on the side (startup costs must be financed)?

A master's degree in a field non aviation related? (also financed)

An A&P or dispatcher certificate...yep you guessed it (financed)

Please don't say all three.... thanks
DK