急! Relocation Fee 要交税吗？

The company gives me 2 choices for relocation fee.

1 They will give me $5000 relocation fee. But HR people told me they also withgold tax for this $5000. so I may get a little bit more than $ 3000. I wonder why I can not get the $ 5000 check instead of after-tax money. I hear the Moviing expense is tax-free.

2. They can reinburse the cost of moving, Up to $8000.

Which Is better? I won't spent much on miving anyway.

Thank you vey much