The true statements about electrical charges are:
- Two negative charges attract each other. (False, they actually repel each other)
- Two positive charges repel each other. (True)
- When a combination of negative and positive charges are present, the charges of opposite signs repel one another. (False, they attract each other)
- Two positive charges attract each other. (False, they repel each other)
Therefore, the correct statement is: Two positive charges repel each other.