Final answer:
The value of the relational expression OAK > PINE in the declared enum Tree { OAK, MAPLE, PINE } is False, because in enums, values are assigned incrementally starting with 0, thus OAK is 0 and PINE is 2.
Step-by-step explanation:
The value of the relational expression OAK > PINE given the enum declaration enum Tree { OAK, MAPLE, PINE }; is False. In this enum, each identifier is assigned an integer value automatically by the compiler, starting with 0 for the first identifier, and incremented by 1 for each subsequent identifier. Since OAK is the first identifier, it would be assigned the value 0, MAPLE would be given the value 1, and PINE would be given the value 2. Comparing OAK to PINE in this context is essentially comparing 0 to 2, which means the statement OAK > PINE is false because 0 is not greater than 2.