Final answer:
The information provided does not specify how many times Yolanda and Selena met before Selena was shot. Further information or sources are needed to determine the number of meetings.
Step-by-step explanation:
Based on the given information, there is no specific mention of how many times Yolanda and Selena met before Selena was shot. The provided information mainly focuses on Yolanda López's background and involvement in activist groups. To determine the number of times they met, it would be necessary to access additional information or sources specific to Yolanda López and Selena's relationship.