2points
which diagram best explains a cause-and-effect relationship that has shaped
u. s. politics?
have
contributed
to
o a. |
restrictions on
who can receive
public campaign
funds
the persistence of
the two-party
system
have
contributed
to
o b.
winner-takes-all
elections
the existence of
many influential
political parties
has
contributed
to
oc.
the advantage of
being an
independent in
congress
the persistence of
the two-party
system

Restrictions for who can receive government campaign money have made a contribution to the continuation of presence of a two-party system.

Option A

Explanation:

The right answer is B, although the diagram best illustrates relationship of cause and effect that has shaped American politics.  

The restrictions on who is eligible for public campaign money have actually helped the two-party system to survive.

There's quite limited public financing for election campaigns in the U.S. so candidates ending up in the private sector.  

In turn, it finances only those who are genuinely liable to get the positions in the vote. This closes the Democratic-Republican question and strengthens the system of two parties.

the government closely monitored its finances to avoid another financial collapse.