Given answer is 100% correct.
1. False : DCFL's are not closed under intersection.
Example:L1={anbncm} intersection L2={ambncn}={anbncn}
2.False: RE is not closed under complement. What does this mean?? It means that the complement may or may not be RE. It is not certain that it will not be RE.
3.False: All languages are countable. Set of languages may be uncountable.
4.False: No language is closed under subset// this reason is correct.
Someone is commented that reguar languages are closed under subset. No, they are not. L=sigma * is regular right? L1={anbncm} is a subset of this language is which is not regular.