TPS7B4250-Q1: Output capacitor selection for TPS7B4250-Q1

Tool/software:

Hello Expert, 

My customer is using TPS7B4250-Q1 and reviewing their external component with car oem.

She is using 2.2uF MLCC on the output of TPS7B4250-Q1. 

Datasheets specifies requirement of output capacitor as below. 

1. VALUE : 1~50Uf
2. ESR : 0.001 ~ 20 ohm

There're no comment about the frequency range of this ESR requires.

Could you please specify which frequency range the ESR should meet the requirement?

Thank you in advance.