The reasonable solution from the options given is:
8 varsity cheerleaders and 4 junior varsity cheerleaders.
This option fits the requirement of selecting a total of 12 cheerleaders, with a proper distribution between the varsity and junior varsity squads.
The other options are not reasonable because:
- 0 varsity and 12 junior varsity cheerleaders: This option works but does not utilize a mix as requested.
- 15 varsity and -3 junior varsity cheerleaders: This option is not reasonable as it involves a negative number of cheerleaders, which is not possible.
- 8 varsity and 8 junior varsity cheerleaders: This totals 16 cheerleaders, which exceeds the requirement.
Therefore, the most reasonable solution is indeed 8 varsity cheerleaders and 4 junior varsity cheerleaders.