For the Poisson GLM in R: The default link function can cause problems by predicting negative counts for some values of the explanatory variable(s) The default link function can cause problems by predicting very large counts for some values of the explanatory variable(s) The default link function is the log The default link function gives a linear relationship between the explanatory variable and the dependent variable The default link function is the identity The default link function gives an exponential relationship between the explanatory variable and the dependent variable