I do not know the UK practice, but the EU rule (that the UK has to apply) says your wife has to present nothing more than het own written statement she has enough funds to study, plus proof of her enrollment (and your marriage certificate for your application).
She does not have to show any money or bank account.

 

Do read art. 7 par. 1 under c and art. 8 par. 3 last - of Directive 2004/38/EC.

Her own written statement will do.