50. What can be the next topic that the author will elaborate? (A) Experiments that argued for ill-measured temperatures, in particular, those influenced by human beings. (B) Measurement errors to be adjusted for the purpose of validating the estimates of temperature trends. (C) Controversies over how to remove artificial warming effects aroused among climate modelers. (D) Schemes that proposed for reconstructing temperature-measuring stations so that heat island effects can be removed.