How Do the VCs Lowlanders Who Ascend to High Altitudes

How do the VCs lowlanders who ascend to high altitudes compared to those born and raised at high altitudes?

A) The VCs of native high altitude residents remain larger
B) After 2-3 days, the VCs are the same size
C) After 2-3 weeks, the VCs are the same size
D) After 2-3 months, the VCs are the same size