Which of the following statements about hash tables is true?

a. A hash table has O(log N) average time to add and search for elements.

b. The higher a hash table’s load factor, the more quickly elements can be found.

c. Once a hash table’s load factor reaches 0.75, no more elements can be added.

d. A hash function maps element values to integer indexes in the hash table.

e. A good hash function returns the same value as much as possible for all data.