Final answer:
The correct statement is that all of the above are correct with respect to conflicting tax laws.
Step-by-step explanation:
The correct statement with respect to conflicting tax laws is d. All of the above are correct.
Regarding statement a, Revenue Rulings and Revenue Procedures seldom are held to be invalid by a court. While they are not binding authority, they are typically given deference by the courts.
Regarding statement b, Regulations are occasionally held to be invalid by a court. This can happen if a court determines that the regulations exceed the authority granted to the agency that issued them.
Regarding statement c, the decisions of higher courts in the judicial hierarchy generally receive additional precedential weight. Lower courts are typically required to follow the decisions of higher courts.