Question: Two variable in the mydata data frame are named Var1 and Var2. How do you tell a bivariate function, such as cor.test, which two variables you want to analyze?

1. `cor.test(Var1 ~ Var2)`
2. `cor.test(mydata$(Var1,Var2))`
3. `cor.test(mydata$Var1,mydata$Var2)`
4. `cor.test(Var1,Var2, mydata)`

Answer: The correct answer of the above question is Option C:`cor.test(mydata$Var1,mydata$Var2)`