Explanation:

- (A): "The issues are" is grammatically correct. It introduces the subject and is appropriately structured.

- (B): "Very complex and the problem" is also correct. It describes the nature of the issues.

- (C): "Is that they are bound to be obscured" is properly used, showing the outcome related to the issues.

- (D): "By these hypocritical politician" contains an error. The word "politician" should be plural to match "these," so it should be "politicians."

- (E): "No Error" would be correct if there were no mistakes in the sentence.

The correct option is:

- 4, (D): There is an error in part (D).