How does DELTA$-$BLAST fix the problem of corruption created by a PSI$-$BLAST search?

Question $8$Answer

a$.$

it removes the corrupted PSSMs

b$.$

it generates a PSSM and then uses this PSSM as a query against the protein database

c$.$

it searches the query against a large database of predefined PSSMs

d$.$

it generates a PSSM that is based upon the results from a search against the CDD$,$ then it uses this PSSM as a query to search a protein database