Utilize the input text as a context reference, choose the right relationship between 'Deloitte' and 'audit' from the options.
Options: stock exchange, distribution format, legal form, product/material produced

Santander has picked PwC to carry out one of the most lucrative audit contracts in banking, ending a relationship with Deloitte that last year generated almost €90m (£63.9m) in fees.
product/material produced