Hi @Eddie
I didn't find any official document that informs that the B family cannot be created with a student signature
reference: https://azure.microsoft.com/pt-br/offers/ms-azr-0170p/
if you just can't find the option, you can click "see all sizes" when creating a new VM:
and then, select B-Series:
If the option does not appear, youcan create a support request on:
https://portal.azure.com/#blade/Microsoft_Azure_Support/HelpAndSupportBlade/overview
Get in touch if you need more help with this issue.
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