In june of 1981, the cdc discovered this new disease in california among the homosexual population.
swine flu
ebola
aids
sars

In June of 1981, the CDC discovered AIDS in California among the homosexual population.  

Explanation:

The AIDS era officially began on June 5, 1981, when the Centers for Disease Control and Prevention (CDC) convened a press conference where they described five cases of Pneumocystis carinii pneumonia in Los Angeles. The following month there were several cases of Kaposi's sarcoma, a type of skin cancer. The first findings of these cases were made by Dr. Michael Gottlieb of San Francisco.

Although doctors knew both Pneumocystis carinii pneumonia and Kaposi's sarcoma, the joint appearance of both in several patients caught their attention. The majority of these patients were sexually active homosexual men, many of whom also suffered from other chronic diseases that were later identified as opportunistic infections. The blood tests that were done on these patients showed that they lacked the proper number of a type of blood cells called CD4 + T cells. Most of these patients died within a few months.

Due to the appearance of pink spots on the body of the infected, the press began to call AIDS, the "pink plague", causing confusion, attributing it to homosexuals, although it was soon noted that Haitian immigrants, injecting drug users and recipients of blood transfusions also suffered from it. In 1982, the new disease was officially named Acquired Immune Deficiency Syndrome (AIDS).

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your answer would be (a)