A state correctional facility for women opens a new self$-$contained unit that houses only offenders in the substance abuse treatment program. The unit has better living conditions than other units of the facility. Inmate Jane requests to be transferred to the new unit and is denied because she has no substance abuse needs. Jane sues the correctional agency, alleging that she is being denied equal protection, and requests a transfer to the facility. A court reviewing Jane's complaint would likely use which equal protection standard to evaluate Jane's case?

Strict scrutiny

Heightened or heightened scrutiny

Rational basis

None, because equal protection is not an issue in prisons.