What distinct characteristics of the HIV/AIDS pandemic enabled its global spread?

Factors that enhance the spread of HIV transmission include migration, economic instability, social and environmental factors, drug use, increased rates of sexually transmitted diseases (STDs), and poverty. In addition, subgroups of the virus may have different rates of transmission (12, 44, 61, 82).

replace   c   with   a   and simplify.

a = c , b = a, q = n , 2 , a = c , 900 b= a , 700 , q = n , 600 , 2 = b o t h , b = a , q = n

it is snorkeling, apex verified.