I did not really consider either number four or number five when I answered this question, but I think both answers are very insightful and absolutely correct.  As a teacher I have seen both strategies used frequently.

African-Americans have long recognized the need for education as a survival strategy and a path to economic success. Organizations like the United Negro College and black colleges founded in response to the Morrill Act of 1890 helped clear the way for blacks to pursue high-quality educations long before desegregation went into effect. This equipped African Americans to rise to positions of wealth and political importance in the US, creating a more positive experience for successive generations.

Certain living arrangements might fit the description of survivial strageties. Moving in with extended family happens in many cultures, including African American cultures, as an economic choice. 

The black church remains the biggest sign of strength and persistence within the black community.  This has a lot more to do with the black community as a whole than the actions of individual "leaders" such as Jackson or Al Sharpton.  The church is the main line of black self-help.

While not easily quantifiable, I think African Americans have combated inequities in the US justice system by bringing national awareness to those issues through the media.  The Trayvon Martin case is just the latest example in a long line of problems that would have likely been swept under the rug if not for the outcry of people due to media coverage.  Instead of being hidden away; however, George Zimmerman has been charged with second degree murder.  I really doubt this happens without the "media mobilization" employed by leaders in the African American community.

One of the survival strategies emerged in the late 1960s and early 1970s, and still has ramifications today. It was the movement for black nationalism, or "black power." African-Americans became convinced that they could not obtain true equality through the gradualism of the civil rights movement, and encouraged community solidarity, especially in northern cities. The extent to which these approaches have persisted can be seen in the name "African-American" itself-it connotes a multiculturalist approach rather than assimilation.

In recent years, African-Americans have largely fought inequalities through raising awareness through media channels. Activists like Jesse Jackson use their national notoriety to draw attention to examples of racial inquality or injustice. The recent Trayvon Martin shooting case is the latest example of this phenomenon. 

What are the signs of strength and persistence of survival strategies that African Americans have adopted in countering social and economic challenges?Some of the social and economic challenges I am interested in are racism, impact of HIV/Aids, rising unemployment, inequities in the US justice system, and health disparities.

I think the importance of the family unit, and the presence of more matriarchal system within the African American community have been important survival strategies. With high and ever increasing rates of incarceration for African American males, it is the women who are the heads of household and the larger extended family unit. These women are the rocks of the society and rely on each other in great deal to continue the family unit. African American families rely on the extended family (aunts, uncles, cousins, grandparents, etc) to survive in a society where the immediate family unit is often broken. 

What are the signs of strength and persistence of survival strategies that African Americans have adopted in countering social and economic challenges?Some of the social and economic challenges I am interested in are racism, impact of HIV/Aids, rising unemployment, inequities in the US justice system, and health disparities.

The main sign of strength and persistence of these survival strategies is the continuing strength of the church in the black community.  The black church has long been one of the most important social institutions in the African American community.  There is some academic controversy about how strong the church still is, but it seems to remain as one of the few legitimate (outside of things like gangs) organizations that remains in the lower-class black community today.  The black church remains as the most obvious example of an African American self-help organization.  It shows that African Americans continue to struggle to improve their status in the face of the social problems that you mention.