2. Socialist systems often have mixed economies because the state
O does not control wealth distribution
O is never certain how the economy will perform
O shares economic control with private enterprise
O is not involved with economic decisions

In the socialist systems the state shares economic control with private enterprise.

Explanation:

The socialist systems are systems where the economy is of mixed type. This is due to the transitional nature of the socialist system, so it has elements of both the system from which it is moving away, and from the system toward it is striding to. In general, it is traditional or market economy from which this system is moving away and transforms into communism, though there are few exceptions that are in the opposite manner.

While the private enterprises are allowed to exist and prosper, there are some limitations, as they are often obligated to be business partners with the state and have to stick to the state's rules. Also, the state is a powerful player on the market, owning and controlling the most important resources and infrastructure.

a and b because with the other three, they simplify to something else.

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