To determine which option is equal to (A ∪ B), we need to understand the meaning of each symbol used.

- A ∪ B represents the union of sets A and B, which includes all elements that are in either A or B or both.
- A ∩ B represents the intersection of sets A and B, which includes all elements that are common to both A and B.
- A` represents the complement of set A, which includes all elements that are not in set A.
- B` represents the complement of set B, which includes all elements that are not in set B.

Now let's evaluate each option:

(a) (A ∩ B): This option represents the intersection of sets A and B. It includes all elements that are common to both sets. However, we want to find the union of sets A and B, so this option is not correct.

(b) A ∪ B`: This option represents the union of set A and the complement of set B. It includes all elements that are in set A and all elements that are not in set B. This option is also not correct because it does not consider elements that may be common to both sets A and B.

(c) A` ∩ B`: This option represents the intersection of the complement of set A and set B. It includes all elements that are not in set A and are in set B. This option is not correct because it does not include elements that are in set A.

(d) none of these: This option seems to be the correct choice because none of the previous options accurately represent the union of sets A and B.

In conclusion, the correct answer is (d) none of these. The union of sets A and B, represented by (A ∪ B), includes all elements that are in either set A or set B or both. None of the given options accurately represent this union.