STP with redundant switches?

I am new to STP and am trying to figure out if it can be used to supply switch redundancy or just link redundancy. Scenario:

- Server with teamed NICs
- Each NIC in the team is going to a different switch
- Each Switch is connected to a main switch

Here is crude diagram:


Will STP work in this situation? Or will there only be 1 path in use here?

If the current path to the server is through switch B, and the A <-> B link goes down, will STP enable the link between A <-> C?

After doing some research my instinct tells me that the answer to the above question is no, STP will not work in this case. To get what I want I need to put Switches B and C in a stack, and at that point STP would work with the stacked switches?

If someone could clarify for me it would be appreciated.

Thanks!