Consider the set N* of finite sequences of natural numbers with a denoting that sequence a is a prefix of sequence b. Then, which of the following is true?
A. Every non-empty subset of has a greatest lower bound
B. It is uncountable
C. Every non-empty finite subset of has a least upper bound
D. Every non-empty subset of has a least upper bound
Answer:A
Consider the set N* of finite sequences of natural numbers with a denoting that sequence a is a prefix of sequence b. Then, which of the following is true?
A. Every non-empty subset of has a greatest lower bound B. It is uncountable C. Every non-empty finite subset of has a least upper bound D. Every non-empty subset of has a least upper bound