How did a geography event weaken the pri’s control over mexican politics ?

Yes

Explanation: Because a number of factors, including the 1994 economic crisis in Mexico, caused the PRI to lose its absolute majority in both chambers of the federal congress for the first time in 1997. After several decades in power the PRI had become a symbol of corruption and electoral fraud.

geography

this is because warmer climates often don't get people sick from the flu and regions where it was often colder more people received the flu. hope this if you need more reasoning i am here to