What is the purpose of block grants or federal aid given to state or local governments?

O federal legislation $($ It is to be contingent on state$/$local endorsement of so$-$called $*$social$"$ It is to be spent on a specific project decided on by the federal, state, and local governments

C It is to be tied to federal mandates that state or local governments must then implement or they will be taxed on the money

It is to be divided into discrete blocks of grants, each limited to $ $100$ million.

$$ It is to be spent in the way the state or local government decides to spend it$,$ within broad parameters.