Hello, I downloaded the B&C Exchange wallet, and want to get my Blockshares

I clicked File and selected Import NuShares wallet. This brought up a box pointed at the Nu directory on my C drive, with various .dat files to choose from:

addr.dat
blk0001.dat
blkindex.dat
walletB.dat
walletC.dat

I do not know which, if any, of these represent my NuShares wallet. Can anyone assist?