Final answer:
The second significant fair housing development of 1968 was Title VIII of the Civil Rights Act, which banned discrimination in the sale or rental of housing.
Step-by-step explanation:
The second significant fair housing development of 1968 is best identified as Title VIII of the Civil Rights Act, also known as the Fair Housing Act of 1968. This Act was a crucial piece of legislation that banned discrimination in the sale or rental of housing. Though other choices like the Federal Housing Administration (FHA) and Section 504 of the Rehabilitation Act are important in their own right, they do not represent the second significant housing development of 1968 in question. The FHA was established long before 1968, and Section 504 came into effect several years later.