a researcher conducting a telephone survey is concerned about possible sources of bias. of the following, which is the best example of nonresponse bias?

How can you keep track of variables in a science experiment?

Ineed to know why d is the correct answer asap

Some mining processes involve removal of large areas of earths surface in the mined region this practice causes severe environmental damage by allowing which natural process to accelerate in the affected areas? a. precipitation b. erosion c. migration d. condensation